source: trunk/essentials/dev-lang/python/Modules/posixmodule.c@ 3368

/* POSIX module implementation */

/* This file is also used for Windows NT/MS-Win and OS/2.  In that case the
   module actually calls itself 'nt' or 'os2', not 'posix', and a few
   functions are either unimplemented or implemented differently.  The source
   assumes that for Windows NT, the macro 'MS_WINDOWS' is defined independent
   of the compiler used.  Different compilers define their own feature
   test macro, e.g. '__BORLANDC__' or '_MSC_VER'.  For OS/2, the compiler
   independent macro PYOS_OS2 should be defined.  On OS/2 the default
   compiler is assumed to be IBM's VisualAge C++ (VACPP).  PYCC_GCC is used
   as the compiler specific macro for the EMX port of gcc to OS/2. */

/* See also ../Dos/dosmodule.c */

#ifdef __APPLE__
   /*
    * Step 1 of support for weak-linking a number of symbols existing on 
    * OSX 10.4 and later, see the comment in the #ifdef __APPLE__ block
    * at the end of this file for more information.
    */
#  pragma weak lchown
#  pragma weak statvfs
#  pragma weak fstatvfs

#endif /* __APPLE__ */

#define PY_SSIZE_T_CLEAN

#include "Python.h"
#include "structseq.h"

#if defined(__VMS)
#    include <unixio.h>
#endif /* defined(__VMS) */

#ifdef __cplusplus
extern "C" {
#endif

PyDoc_STRVAR(posix__doc__,
"This module provides access to operating system functionality that is\n\
standardized by the C Standard and the POSIX standard (a thinly\n\
disguised Unix interface).  Refer to the library manual and\n\
corresponding Unix manual entries for more information on calls.");

#ifndef Py_USING_UNICODE
/* This is used in signatures of functions. */
#define Py_UNICODE void
#endif

#if defined(PYOS_OS2)
#define  INCL_DOS
#define  INCL_DOSERRORS
#define  INCL_DOSPROCESS
#define  INCL_NOPMAPI
#include <os2.h>
#if defined(PYCC_GCC)
#include <ctype.h>
#include <io.h>
#include <stdio.h>
#include <process.h>
#endif
#include "osdefs.h"
#endif

#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif /* HAVE_SYS_TYPES_H */

#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif /* HAVE_SYS_STAT_H */

#ifdef HAVE_SYS_WAIT_H
#include <sys/wait.h>           /* For WNOHANG */
#endif

#ifdef HAVE_SIGNAL_H
#include <signal.h>
#endif

#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif /* HAVE_FCNTL_H */

#ifdef HAVE_GRP_H
#include <grp.h>
#endif

#ifdef HAVE_SYSEXITS_H
#include <sysexits.h>
#endif /* HAVE_SYSEXITS_H */

#ifdef HAVE_SYS_LOADAVG_H
#include <sys/loadavg.h>
#endif

/* Various compilers have only certain posix functions */
/* XXX Gosh I wish these were all moved into pyconfig.h */
#if defined(PYCC_VACPP) && defined(PYOS_OS2)
#include <process.h>
#else
#if defined(__WATCOMC__) && !defined(__QNX__)           /* Watcom compiler */
#define HAVE_GETCWD     1
#define HAVE_OPENDIR    1
#define HAVE_SYSTEM     1
#if defined(__OS2__)
#define HAVE_EXECV      1
#define HAVE_WAIT       1
#endif
#include <process.h>
#else
#ifdef __BORLANDC__             /* Borland compiler */
#define HAVE_EXECV      1
#define HAVE_GETCWD     1
#define HAVE_OPENDIR    1
#define HAVE_PIPE       1
#define HAVE_POPEN      1
#define HAVE_SYSTEM     1
#define HAVE_WAIT       1
#else
#ifdef _MSC_VER         /* Microsoft compiler */
#define HAVE_GETCWD     1
#define HAVE_SPAWNV     1
#define HAVE_EXECV      1
#define HAVE_PIPE       1
#define HAVE_POPEN      1
#define HAVE_SYSTEM     1
#define HAVE_CWAIT      1
#define HAVE_FSYNC      1
#define fsync _commit
#else
#if (defined(PYOS_OS2) && defined(PYCC_GCC) && !defined(__KLIBC__)) || defined(__VMS)
/* Everything needed is defined in PC/os2emx/pyconfig.h or vms/pyconfig.h */
#else                   /* all other compilers */
/* Unix functions that the configure script doesn't check for */
#define HAVE_EXECV      1
#define HAVE_FORK       1
#if defined(__USLC__) && defined(__SCO_VERSION__)       /* SCO UDK Compiler */
#define HAVE_FORK1      1
#endif
#define HAVE_GETCWD     1
#define HAVE_GETEGID    1
#define HAVE_GETEUID    1
#define HAVE_GETGID     1
#define HAVE_GETPPID    1
#define HAVE_GETUID     1
#define HAVE_KILL       1
#define HAVE_OPENDIR    1
#define HAVE_PIPE       1
#ifndef __rtems__
#define HAVE_POPEN      1
#endif
#define HAVE_SYSTEM     1
#define HAVE_WAIT       1
#define HAVE_TTYNAME    1
#endif  /* PYOS_OS2 && PYCC_GCC && __VMS */
#endif  /* _MSC_VER */
#endif  /* __BORLANDC__ */
#endif  /* ! __WATCOMC__ || __QNX__ */
#endif /* ! __IBMC__ */

#ifndef _MSC_VER

#if defined(__sgi)&&_COMPILER_VERSION>=700
/* declare ctermid_r if compiling with MIPSPro 7.x in ANSI C mode
   (default) */
extern char        *ctermid_r(char *);
#endif

#ifndef HAVE_UNISTD_H
#if defined(PYCC_VACPP)
extern int mkdir(char *);
#else
#if ( defined(__WATCOMC__) || defined(_MSC_VER) ) && !defined(__QNX__)
extern int mkdir(const char *);
#else
extern int mkdir(const char *, mode_t);
#endif
#endif
#if defined(__IBMC__) || defined(__IBMCPP__)
extern int chdir(char *);
extern int rmdir(char *);
#else
extern int chdir(const char *);
extern int rmdir(const char *);
#endif
#ifdef __BORLANDC__
extern int chmod(const char *, int);
#else
extern int chmod(const char *, mode_t);
#endif
extern int chown(const char *, uid_t, gid_t);
extern char *getcwd(char *, int);
extern char *strerror(int);
extern int link(const char *, const char *);
extern int rename(const char *, const char *);
extern int stat(const char *, struct stat *);
extern int unlink(const char *);
extern int pclose(FILE *);
#ifdef HAVE_SYMLINK
extern int symlink(const char *, const char *);
#endif /* HAVE_SYMLINK */
#ifdef HAVE_LSTAT
extern int lstat(const char *, struct stat *);
#endif /* HAVE_LSTAT */
#endif /* !HAVE_UNISTD_H */

#endif /* !_MSC_VER */

#ifdef HAVE_UTIME_H
#include <utime.h>
#endif /* HAVE_UTIME_H */

#ifdef HAVE_SYS_UTIME_H
#include <sys/utime.h>
#define HAVE_UTIME_H /* pretend we do for the rest of this file */
#endif /* HAVE_SYS_UTIME_H */

#ifdef HAVE_SYS_TIMES_H
#include <sys/times.h>
#endif /* HAVE_SYS_TIMES_H */

#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif /* HAVE_SYS_PARAM_H */

#ifdef HAVE_SYS_UTSNAME_H
#include <sys/utsname.h>
#endif /* HAVE_SYS_UTSNAME_H */

#ifdef HAVE_DIRENT_H
#include <dirent.h>
#define NAMLEN(dirent) strlen((dirent)->d_name)
#else
#if defined(__WATCOMC__) && !defined(__QNX__)
#include <direct.h>
#define NAMLEN(dirent) strlen((dirent)->d_name)
#else
#define dirent direct
#define NAMLEN(dirent) (dirent)->d_namlen
#endif
#ifdef HAVE_SYS_NDIR_H
#include <sys/ndir.h>
#endif
#ifdef HAVE_SYS_DIR_H
#include <sys/dir.h>
#endif
#ifdef HAVE_NDIR_H
#include <ndir.h>
#endif
#endif

#ifdef _MSC_VER
#ifdef HAVE_DIRECT_H
#include <direct.h>
#endif
#ifdef HAVE_IO_H
#include <io.h>
#endif
#ifdef HAVE_PROCESS_H
#include <process.h>
#endif
#include "osdefs.h"
#define _WIN32_WINNT 0x0400       /* Needed for CryptoAPI on some systems */
#include <windows.h>
#include <shellapi.h>   /* for ShellExecute() */
#define popen   _popen
#define pclose  _pclose
#endif /* _MSC_VER */

#if defined(PYCC_VACPP) && defined(PYOS_OS2)
#include <io.h>
#endif /* OS2 */

#ifndef MAXPATHLEN
#if defined(PATH_MAX) && PATH_MAX > 1024
#define MAXPATHLEN PATH_MAX
#else
#define MAXPATHLEN 1024
#endif
#endif /* MAXPATHLEN */

#ifdef UNION_WAIT
/* Emulate some macros on systems that have a union instead of macros */

#ifndef WIFEXITED
#define WIFEXITED(u_wait) (!(u_wait).w_termsig && !(u_wait).w_coredump)
#endif

#ifndef WEXITSTATUS
#define WEXITSTATUS(u_wait) (WIFEXITED(u_wait)?((u_wait).w_retcode):-1)
#endif

#ifndef WTERMSIG
#define WTERMSIG(u_wait) ((u_wait).w_termsig)
#endif

#define WAIT_TYPE union wait
#define WAIT_STATUS_INT(s) (s.w_status)

#else /* !UNION_WAIT */
#define WAIT_TYPE int
#define WAIT_STATUS_INT(s) (s)
#endif /* UNION_WAIT */

/* Don't use the "_r" form if we don't need it (also, won't have a
   prototype for it, at least on Solaris -- maybe others as well?). */
#if defined(HAVE_CTERMID_R) && defined(WITH_THREAD)
#define USE_CTERMID_R
#endif

#if defined(HAVE_TMPNAM_R) && defined(WITH_THREAD)
#define USE_TMPNAM_R
#endif

/* choose the appropriate stat and fstat functions and return structs */
#undef STAT
#if defined(MS_WIN64) || defined(MS_WINDOWS)
#       define STAT win32_stat
#       define FSTAT win32_fstat
#       define STRUCT_STAT struct win32_stat
#else
#       define STAT stat
#       define FSTAT fstat
#       define STRUCT_STAT struct stat
#endif

#if defined(MAJOR_IN_MKDEV)
#include <sys/mkdev.h>
#else
#if defined(MAJOR_IN_SYSMACROS)
#include <sys/sysmacros.h>
#endif
#if defined(HAVE_MKNOD) && defined(HAVE_SYS_MKDEV_H)
#include <sys/mkdev.h>
#endif
#endif

/* Return a dictionary corresponding to the POSIX environment table */
#ifdef WITH_NEXT_FRAMEWORK
/* On Darwin/MacOSX a shared library or framework has no access to
** environ directly, we must obtain it with _NSGetEnviron().
*/
#include <crt_externs.h>
static char **environ;
#elif !defined(_MSC_VER) && ( !defined(__WATCOMC__) || defined(__QNX__) )
extern char **environ;
#endif /* !_MSC_VER */

static PyObject *
convertenviron(void)
{
        PyObject *d;
        char **e;
        d = PyDict_New();
        if (d == NULL)
                return NULL;
#ifdef WITH_NEXT_FRAMEWORK
        if (environ == NULL)
                environ = *_NSGetEnviron();
#endif
        if (environ == NULL)
                return d;
        /* This part ignores errors */
        for (e = environ; *e != NULL; e++) {
                PyObject *k;
                PyObject *v;
                char *p = strchr(*e, '=');
                if (p == NULL)
                        continue;
                k = PyString_FromStringAndSize(*e, (int)(p-*e));
                if (k == NULL) {
                        PyErr_Clear();
                        continue;
                }
                v = PyString_FromString(p+1);
                if (v == NULL) {
                        PyErr_Clear();
                        Py_DECREF(k);
                        continue;
                }
                if (PyDict_GetItem(d, k) == NULL) {
                        if (PyDict_SetItem(d, k, v) != 0)
                                PyErr_Clear();
                }
                Py_DECREF(k);
                Py_DECREF(v);
        }
#if defined(PYOS_OS2)
    {
        APIRET rc;
        char   buffer[1024]; /* OS/2 Provides a Documented Max of 1024 Chars */

        rc = DosQueryExtLIBPATH(buffer, BEGIN_LIBPATH);
        if (rc == NO_ERROR) { /* (not a type, envname is NOT 'BEGIN_LIBPATH') */
            PyObject *v = PyString_FromString(buffer);
                    PyDict_SetItemString(d, "BEGINLIBPATH", v);
            Py_DECREF(v);
        }
        rc = DosQueryExtLIBPATH(buffer, END_LIBPATH);
        if (rc == NO_ERROR) { /* (not a typo, envname is NOT 'END_LIBPATH') */
            PyObject *v = PyString_FromString(buffer);
                    PyDict_SetItemString(d, "ENDLIBPATH", v);
            Py_DECREF(v);
        }
    }
#endif
        return d;
}


/* Set a POSIX-specific error from errno, and return NULL */

static PyObject *
posix_error(void)
{
        return PyErr_SetFromErrno(PyExc_OSError);
}
static PyObject *
posix_error_with_filename(char* name)
{
        return PyErr_SetFromErrnoWithFilename(PyExc_OSError, name);
}

#ifdef Py_WIN_WIDE_FILENAMES
static PyObject *
posix_error_with_unicode_filename(Py_UNICODE* name)
{
        return PyErr_SetFromErrnoWithUnicodeFilename(PyExc_OSError, name);
}
#endif /* Py_WIN_WIDE_FILENAMES */


static PyObject *
posix_error_with_allocated_filename(char* name)
{
        PyObject *rc = PyErr_SetFromErrnoWithFilename(PyExc_OSError, name);
        PyMem_Free(name);
        return rc;
}

#ifdef MS_WINDOWS
static PyObject *
win32_error(char* function, char* filename)
{
        /* XXX We should pass the function name along in the future.
           (_winreg.c also wants to pass the function name.)
           This would however require an additional param to the
           Windows error object, which is non-trivial.
        */
        errno = GetLastError();
        if (filename)
                return PyErr_SetFromWindowsErrWithFilename(errno, filename);
        else
                return PyErr_SetFromWindowsErr(errno);
}

#ifdef Py_WIN_WIDE_FILENAMES
static PyObject *
win32_error_unicode(char* function, Py_UNICODE* filename)
{
        /* XXX - see win32_error for comments on 'function' */
        errno = GetLastError();
        if (filename)
                return PyErr_SetFromWindowsErrWithUnicodeFilename(errno, filename);
        else
                return PyErr_SetFromWindowsErr(errno);
}

static PyObject *_PyUnicode_FromFileSystemEncodedObject(register PyObject *obj)
{
}

/* Function suitable for O& conversion */
static int
convert_to_unicode(PyObject *arg, void* _param)
{
        PyObject **param = (PyObject**)_param;
        if (PyUnicode_CheckExact(arg)) {
                Py_INCREF(arg);
                *param = arg;
        } 
        else if (PyUnicode_Check(arg)) {
                /* For a Unicode subtype that's not a Unicode object,
                   return a true Unicode object with the same data. */
                *param = PyUnicode_FromUnicode(PyUnicode_AS_UNICODE(arg),
                                               PyUnicode_GET_SIZE(arg));
                return *param != NULL;
        }
        else
                *param = PyUnicode_FromEncodedObject(arg,
                                                     Py_FileSystemDefaultEncoding,
                                                     "strict");
        return (*param) != NULL;
}

#endif /* Py_WIN_WIDE_FILENAMES */

#endif

#if defined(PYOS_OS2)
/**********************************************************************
 *         Helper Function to Trim and Format OS/2 Messages
 **********************************************************************/
    static void
os2_formatmsg(char *msgbuf, int msglen, char *reason)
{
    msgbuf[msglen] = '\0'; /* OS/2 Doesn't Guarantee a Terminator */

    if (strlen(msgbuf) > 0) { /* If Non-Empty Msg, Trim CRLF */
        char *lastc = &msgbuf[ strlen(msgbuf)-1 ];

        while (lastc > msgbuf && isspace(Py_CHARMASK(*lastc)))
            *lastc-- = '\0'; /* Trim Trailing Whitespace (CRLF) */
    }

    /* Add Optional Reason Text */
    if (reason) {
        strcat(msgbuf, " : ");
        strcat(msgbuf, reason);
    }
}

/**********************************************************************
 *             Decode an OS/2 Operating System Error Code
 *
 * A convenience function to lookup an OS/2 error code and return a
 * text message we can use to raise a Python exception.
 *
 * Notes:
 *   The messages for errors returned from the OS/2 kernel reside in
 *   the file OSO001.MSG in the \OS2 directory hierarchy.
 *
 **********************************************************************/
    static char *
os2_strerror(char *msgbuf, int msgbuflen, int errorcode, char *reason)
{
    APIRET rc;
    ULONG  msglen;

    /* Retrieve Kernel-Related Error Message from OSO001.MSG File */
    Py_BEGIN_ALLOW_THREADS
    rc = DosGetMessage(NULL, 0, msgbuf, msgbuflen,
                       errorcode, "oso001.msg", &msglen);
    Py_END_ALLOW_THREADS

    if (rc == NO_ERROR)
        os2_formatmsg(msgbuf, msglen, reason);
    else
        PyOS_snprintf(msgbuf, msgbuflen,
                      "unknown OS error #%d", errorcode);

    return msgbuf;
}

/* Set an OS/2-specific error and return NULL.  OS/2 kernel
   errors are not in a global variable e.g. 'errno' nor are
   they congruent with posix error numbers. */

static PyObject * os2_error(int code)
{
    char text[1024];
    PyObject *v;

    os2_strerror(text, sizeof(text), code, "");

    v = Py_BuildValue("(is)", code, text);
    if (v != NULL) {
        PyErr_SetObject(PyExc_OSError, v);
        Py_DECREF(v);
    }
    return NULL; /* Signal to Python that an Exception is Pending */
}

#endif /* OS2 */

/* POSIX generic methods */

static PyObject *
posix_fildes(PyObject *fdobj, int (*func)(int))
{
        int fd;
        int res;
        fd = PyObject_AsFileDescriptor(fdobj);
        if (fd < 0)
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        res = (*func)(fd);
        Py_END_ALLOW_THREADS
        if (res < 0)
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}

#ifdef Py_WIN_WIDE_FILENAMES
static int
unicode_file_names(void)
{
        static int canusewide = -1;
        if (canusewide == -1) {
                /* As per doc for ::GetVersion(), this is the correct test for
                   the Windows NT family. */
                canusewide = (GetVersion() < 0x80000000) ? 1 : 0;
        }
        return canusewide;
}
#endif

static PyObject *
posix_1str(PyObject *args, char *format, int (*func)(const char*))
{
        char *path1 = NULL;
        int res;
        if (!PyArg_ParseTuple(args, format,
                              Py_FileSystemDefaultEncoding, &path1))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        res = (*func)(path1);
        Py_END_ALLOW_THREADS
        if (res < 0)
                return posix_error_with_allocated_filename(path1);
        PyMem_Free(path1);
        Py_INCREF(Py_None);
        return Py_None;
}

static PyObject *
posix_2str(PyObject *args,
           char *format,
           int (*func)(const char *, const char *))
{
        char *path1 = NULL, *path2 = NULL;
        int res;
        if (!PyArg_ParseTuple(args, format,
                              Py_FileSystemDefaultEncoding, &path1,
                              Py_FileSystemDefaultEncoding, &path2))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        res = (*func)(path1, path2);
        Py_END_ALLOW_THREADS
        PyMem_Free(path1);
        PyMem_Free(path2);
        if (res != 0)
                /* XXX how to report both path1 and path2??? */
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}

#ifdef Py_WIN_WIDE_FILENAMES
static PyObject*
win32_1str(PyObject* args, char* func, 
           char* format, BOOL (__stdcall *funcA)(LPCSTR), 
           char* wformat, BOOL (__stdcall *funcW)(LPWSTR))
{
        PyObject *uni;
        char *ansi;
        BOOL result;
        if (unicode_file_names()) {
                if (!PyArg_ParseTuple(args, wformat, &uni))
                        PyErr_Clear();
                else {
                        Py_BEGIN_ALLOW_THREADS
                        result = funcW(PyUnicode_AsUnicode(uni));
                        Py_END_ALLOW_THREADS
                        if (!result)
                                return win32_error_unicode(func, PyUnicode_AsUnicode(uni));
                        Py_INCREF(Py_None);
                        return Py_None;
                }
        }
        if (!PyArg_ParseTuple(args, format, &ansi))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        result = funcA(ansi);
        Py_END_ALLOW_THREADS
        if (!result)
                return win32_error(func, ansi);
        Py_INCREF(Py_None);
        return Py_None;

}

/* This is a reimplementation of the C library's chdir function,
   but one that produces Win32 errors instead of DOS error codes.
   chdir is essentially a wrapper around SetCurrentDirectory; however,
   it also needs to set "magic" environment variables indicating
   the per-drive current directory, which are of the form =<drive>: */
BOOL __stdcall
win32_chdir(LPCSTR path)
{
        char new_path[MAX_PATH+1];
        int result;
        char env[4] = "=x:";

        if(!SetCurrentDirectoryA(path))
                return FALSE;
        result = GetCurrentDirectoryA(MAX_PATH+1, new_path);
        if (!result)
                return FALSE;
        /* In the ANSI API, there should not be any paths longer
           than MAX_PATH. */
        assert(result <= MAX_PATH+1);
        if (strncmp(new_path, "\\\\", 2) == 0 ||
            strncmp(new_path, "//", 2) == 0)
            /* UNC path, nothing to do. */
            return TRUE;
        env[1] = new_path[0];
        return SetEnvironmentVariableA(env, new_path);
}

/* The Unicode version differs from the ANSI version
   since the current directory might exceed MAX_PATH characters */
BOOL __stdcall
win32_wchdir(LPCWSTR path)
{
        wchar_t _new_path[MAX_PATH+1], *new_path = _new_path;
        int result;
        wchar_t env[4] = L"=x:";

        if(!SetCurrentDirectoryW(path))
                return FALSE;
        result = GetCurrentDirectoryW(MAX_PATH+1, new_path);
        if (!result)
                return FALSE;
        if (result > MAX_PATH+1) {
                new_path = malloc(result);
                if (!new_path) {
                        SetLastError(ERROR_OUTOFMEMORY);
                        return FALSE;
                }
        }
        if (wcsncmp(new_path, L"\\\\", 2) == 0 ||
            wcsncmp(new_path, L"//", 2) == 0)
            /* UNC path, nothing to do. */
            return TRUE;
        env[1] = new_path[0];
        result = SetEnvironmentVariableW(env, new_path);
        if (new_path != _new_path)
                free(new_path);
        return result;
}
#endif

#ifdef MS_WINDOWS
/* The CRT of Windows has a number of flaws wrt. its stat() implementation:
   - time stamps are restricted to second resolution
   - file modification times suffer from forth-and-back conversions between
     UTC and local time
   Therefore, we implement our own stat, based on the Win32 API directly.
*/
#define HAVE_STAT_NSEC 1 

struct win32_stat{
    int st_dev;
    __int64 st_ino;
    unsigned short st_mode;
    int st_nlink;
    int st_uid;
    int st_gid;
    int st_rdev;
    __int64 st_size;
    int st_atime;
    int st_atime_nsec;
    int st_mtime;
    int st_mtime_nsec;
    int st_ctime;
    int st_ctime_nsec;
};

static __int64 secs_between_epochs = 11644473600; /* Seconds between 1.1.1601 and 1.1.1970 */

static void
FILE_TIME_to_time_t_nsec(FILETIME *in_ptr, int *time_out, int* nsec_out)
{
        /* XXX endianness. Shouldn't matter, as all Windows implementations are little-endian */
        /* Cannot simply cast and dereference in_ptr, 
           since it might not be aligned properly */
        __int64 in;
        memcpy(&in, in_ptr, sizeof(in));
        *nsec_out = (int)(in % 10000000) * 100; /* FILETIME is in units of 100 nsec. */
        /* XXX Win32 supports time stamps past 2038; we currently don't */
        *time_out = Py_SAFE_DOWNCAST((in / 10000000) - secs_between_epochs, __int64, int);
}

static void
time_t_to_FILE_TIME(int time_in, int nsec_in, FILETIME *out_ptr)
{
        /* XXX endianness */
        __int64 out;
        out = time_in + secs_between_epochs;
        out = out * 10000000 + nsec_in;
        memcpy(out_ptr, &out, sizeof(out));
}

/* Below, we *know* that ugo+r is 0444 */
#if _S_IREAD != 0400
#error Unsupported C library
#endif
static int
attributes_to_mode(DWORD attr)
{
        int m = 0;
        if (attr & FILE_ATTRIBUTE_DIRECTORY)
                m |= _S_IFDIR | 0111; /* IFEXEC for user,group,other */
        else
                m |= _S_IFREG;
        if (attr & FILE_ATTRIBUTE_READONLY)
                m |= 0444;
        else
                m |= 0666;
        return m;
}

static int
attribute_data_to_stat(WIN32_FILE_ATTRIBUTE_DATA *info, struct win32_stat *result)
{
        memset(result, 0, sizeof(*result));
        result->st_mode = attributes_to_mode(info->dwFileAttributes);
        result->st_size = (((__int64)info->nFileSizeHigh)<<32) + info->nFileSizeLow;
        FILE_TIME_to_time_t_nsec(&info->ftCreationTime, &result->st_ctime, &result->st_ctime_nsec);
        FILE_TIME_to_time_t_nsec(&info->ftLastWriteTime, &result->st_mtime, &result->st_mtime_nsec);
        FILE_TIME_to_time_t_nsec(&info->ftLastAccessTime, &result->st_atime, &result->st_atime_nsec);

        return 0;
}

static int 
win32_stat(const char* path, struct win32_stat *result)
{
        WIN32_FILE_ATTRIBUTE_DATA info;
        int code;
        char *dot;
        /* XXX not supported on Win95 and NT 3.x */
        if (!GetFileAttributesExA(path, GetFileExInfoStandard, &info)) {
                /* Protocol violation: we explicitly clear errno, instead of
                   setting it to a POSIX error. Callers should use GetLastError. */
                errno = 0;
                return -1;
        }
        code = attribute_data_to_stat(&info, result);
        if (code != 0)
                return code;
        /* Set S_IFEXEC if it is an .exe, .bat, ... */
        dot = strrchr(path, '.');
        if (dot) {
                if (stricmp(dot, ".bat") == 0 ||
                stricmp(dot, ".cmd") == 0 ||
                stricmp(dot, ".exe") == 0 ||
                stricmp(dot, ".com") == 0)
                result->st_mode |= 0111;
        }
        return code;
}

static int 
win32_wstat(const wchar_t* path, struct win32_stat *result)
{
        int code;
        const wchar_t *dot;
        WIN32_FILE_ATTRIBUTE_DATA info;
        /* XXX not supported on Win95 and NT 3.x */
        if (!GetFileAttributesExW(path, GetFileExInfoStandard, &info)) {
                /* Protocol violation: we explicitly clear errno, instead of
                   setting it to a POSIX error. Callers should use GetLastError. */
                errno = 0;
                return -1;
        }
        code = attribute_data_to_stat(&info, result);
        if (code < 0)
                return code;
        /* Set IFEXEC if it is an .exe, .bat, ... */
        dot = wcsrchr(path, '.');
        if (dot) {
                if (_wcsicmp(dot, L".bat") == 0 ||
                    _wcsicmp(dot, L".cmd") == 0 ||
                    _wcsicmp(dot, L".exe") == 0 ||
                    _wcsicmp(dot, L".com") == 0)
                        result->st_mode |= 0111;
        }
        return code;
}

static int
win32_fstat(int file_number, struct win32_stat *result)
{
        BY_HANDLE_FILE_INFORMATION info;
        HANDLE h;
        int type;
    
        h = (HANDLE)_get_osfhandle(file_number);
    
        /* Protocol violation: we explicitly clear errno, instead of
           setting it to a POSIX error. Callers should use GetLastError. */
        errno = 0;

        if (h == INVALID_HANDLE_VALUE) {
                /* This is really a C library error (invalid file handle).
                   We set the Win32 error to the closes one matching. */
                SetLastError(ERROR_INVALID_HANDLE);
                return -1;
        }
        memset(result, 0, sizeof(*result));

        type = GetFileType(h);
        if (type == FILE_TYPE_UNKNOWN) {
            DWORD error = GetLastError();
            if (error != 0) {
                return -1;
            }
            /* else: valid but unknown file */
        }

        if (type != FILE_TYPE_DISK) {
                if (type == FILE_TYPE_CHAR)
                        result->st_mode = _S_IFCHR;
                else if (type == FILE_TYPE_PIPE)
                        result->st_mode = _S_IFIFO;
                return 0;
        }

        if (!GetFileInformationByHandle(h, &info)) {
                return -1;
        }

        /* similar to stat() */
        result->st_mode = attributes_to_mode(info.dwFileAttributes);
        result->st_size = (((__int64)info.nFileSizeHigh)<<32) + info.nFileSizeLow;
        FILE_TIME_to_time_t_nsec(&info.ftCreationTime, &result->st_ctime, &result->st_ctime_nsec);
        FILE_TIME_to_time_t_nsec(&info.ftLastWriteTime, &result->st_mtime, &result->st_mtime_nsec);
        FILE_TIME_to_time_t_nsec(&info.ftLastAccessTime, &result->st_atime, &result->st_atime_nsec);
        /* specific to fstat() */
        result->st_nlink = info.nNumberOfLinks;
        result->st_ino = (((__int64)info.nFileIndexHigh)<<32) + info.nFileIndexLow;
        return 0;
}

#endif /* MS_WINDOWS */

PyDoc_STRVAR(stat_result__doc__,
"stat_result: Result from stat or lstat.\n\n\
This object may be accessed either as a tuple of\n\
  (mode, ino, dev, nlink, uid, gid, size, atime, mtime, ctime)\n\
or via the attributes st_mode, st_ino, st_dev, st_nlink, st_uid, and so on.\n\
\n\
Posix/windows: If your platform supports st_blksize, st_blocks, st_rdev,\n\
or st_flags, they are available as attributes only.\n\
\n\
See os.stat for more information.");

static PyStructSequence_Field stat_result_fields[] = {
        {"st_mode",    "protection bits"},
        {"st_ino",     "inode"},
        {"st_dev",     "device"},
        {"st_nlink",   "number of hard links"},
        {"st_uid",     "user ID of owner"},
        {"st_gid",     "group ID of owner"},
        {"st_size",    "total size, in bytes"},
        /* The NULL is replaced with PyStructSequence_UnnamedField later. */
        {NULL,   "integer time of last access"},
        {NULL,   "integer time of last modification"},
        {NULL,   "integer time of last change"},
        {"st_atime",   "time of last access"},
        {"st_mtime",   "time of last modification"},
        {"st_ctime",   "time of last change"},
#ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
        {"st_blksize", "blocksize for filesystem I/O"},
#endif
#ifdef HAVE_STRUCT_STAT_ST_BLOCKS
        {"st_blocks",  "number of blocks allocated"},
#endif
#ifdef HAVE_STRUCT_STAT_ST_RDEV
        {"st_rdev",    "device type (if inode device)"},
#endif
#ifdef HAVE_STRUCT_STAT_ST_FLAGS
        {"st_flags",   "user defined flags for file"},
#endif
#ifdef HAVE_STRUCT_STAT_ST_GEN
        {"st_gen",    "generation number"},
#endif
#ifdef HAVE_STRUCT_STAT_ST_BIRTHTIME
        {"st_birthtime",   "time of creation"},
#endif
        {0}
};

#ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
#define ST_BLKSIZE_IDX 13
#else
#define ST_BLKSIZE_IDX 12
#endif

#ifdef HAVE_STRUCT_STAT_ST_BLOCKS
#define ST_BLOCKS_IDX (ST_BLKSIZE_IDX+1)
#else
#define ST_BLOCKS_IDX ST_BLKSIZE_IDX
#endif

#ifdef HAVE_STRUCT_STAT_ST_RDEV
#define ST_RDEV_IDX (ST_BLOCKS_IDX+1)
#else
#define ST_RDEV_IDX ST_BLOCKS_IDX
#endif

#ifdef HAVE_STRUCT_STAT_ST_FLAGS
#define ST_FLAGS_IDX (ST_RDEV_IDX+1)
#else
#define ST_FLAGS_IDX ST_RDEV_IDX
#endif

#ifdef HAVE_STRUCT_STAT_ST_GEN
#define ST_GEN_IDX (ST_FLAGS_IDX+1)
#else
#define ST_GEN_IDX ST_FLAGS_IDX
#endif

#ifdef HAVE_STRUCT_STAT_ST_BIRTHTIME
#define ST_BIRTHTIME_IDX (ST_GEN_IDX+1)
#else
#define ST_BIRTHTIME_IDX ST_GEN_IDX
#endif

static PyStructSequence_Desc stat_result_desc = {
        "stat_result", /* name */
        stat_result__doc__, /* doc */
        stat_result_fields,
        10
};

PyDoc_STRVAR(statvfs_result__doc__,
"statvfs_result: Result from statvfs or fstatvfs.\n\n\
This object may be accessed either as a tuple of\n\
  (bsize, frsize, blocks, bfree, bavail, files, ffree, favail, flag, namemax),\n\
or via the attributes f_bsize, f_frsize, f_blocks, f_bfree, and so on.\n\
\n\
See os.statvfs for more information.");

static PyStructSequence_Field statvfs_result_fields[] = {
        {"f_bsize",  },
        {"f_frsize", },
        {"f_blocks", },
        {"f_bfree",  },
        {"f_bavail", },
        {"f_files",  },
        {"f_ffree",  },
        {"f_favail", },
        {"f_flag",   },
        {"f_namemax",},
        {0}
};

static PyStructSequence_Desc statvfs_result_desc = {
        "statvfs_result", /* name */
        statvfs_result__doc__, /* doc */
        statvfs_result_fields,
        10
};

static int initialized;
static PyTypeObject StatResultType;
static PyTypeObject StatVFSResultType;
static newfunc structseq_new;

static PyObject *
statresult_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
        PyStructSequence *result;
        int i;

        result = (PyStructSequence*)structseq_new(type, args, kwds);
        if (!result)
                return NULL;
        /* If we have been initialized from a tuple,
           st_?time might be set to None. Initialize it
           from the int slots.  */
        for (i = 7; i <= 9; i++) {
                if (result->ob_item[i+3] == Py_None) {
                        Py_DECREF(Py_None);
                        Py_INCREF(result->ob_item[i]);
                        result->ob_item[i+3] = result->ob_item[i];
                }
        }
        return (PyObject*)result;
}



/* If true, st_?time is float. */
static int _stat_float_times = 1;

PyDoc_STRVAR(stat_float_times__doc__,
"stat_float_times([newval]) -> oldval\n\n\
Determine whether os.[lf]stat represents time stamps as float objects.\n\
If newval is True, future calls to stat() return floats, if it is False,\n\
future calls return ints. \n\
If newval is omitted, return the current setting.\n");

static PyObject*
stat_float_times(PyObject* self, PyObject *args)
{
        int newval = -1;
        if (!PyArg_ParseTuple(args, "|i:stat_float_times", &newval))
                return NULL;
        if (newval == -1)
                /* Return old value */
                return PyBool_FromLong(_stat_float_times);
        _stat_float_times = newval;
        Py_INCREF(Py_None);
        return Py_None;
}

static void
fill_time(PyObject *v, int index, time_t sec, unsigned long nsec)
{
        PyObject *fval,*ival;
#if SIZEOF_TIME_T > SIZEOF_LONG
        ival = PyLong_FromLongLong((PY_LONG_LONG)sec);
#else
        ival = PyInt_FromLong((long)sec);
#endif
        if (!ival)
                return;
        if (_stat_float_times) {
                fval = PyFloat_FromDouble(sec + 1e-9*nsec);
        } else {
                fval = ival;
                Py_INCREF(fval);
        }
        PyStructSequence_SET_ITEM(v, index, ival);
        PyStructSequence_SET_ITEM(v, index+3, fval);
}

/* pack a system stat C structure into the Python stat tuple
   (used by posix_stat() and posix_fstat()) */
static PyObject*
_pystat_fromstructstat(STRUCT_STAT *st)
{
        unsigned long ansec, mnsec, cnsec;
        PyObject *v = PyStructSequence_New(&StatResultType);
        if (v == NULL)
                return NULL;

        PyStructSequence_SET_ITEM(v, 0, PyInt_FromLong((long)st->st_mode));
#ifdef HAVE_LARGEFILE_SUPPORT
        PyStructSequence_SET_ITEM(v, 1,
                                  PyLong_FromLongLong((PY_LONG_LONG)st->st_ino));
#else
        PyStructSequence_SET_ITEM(v, 1, PyInt_FromLong((long)st->st_ino));
#endif
#if defined(HAVE_LONG_LONG) && !defined(MS_WINDOWS)
        PyStructSequence_SET_ITEM(v, 2,
                                  PyLong_FromLongLong((PY_LONG_LONG)st->st_dev));
#else
        PyStructSequence_SET_ITEM(v, 2, PyInt_FromLong((long)st->st_dev));
#endif
        PyStructSequence_SET_ITEM(v, 3, PyInt_FromLong((long)st->st_nlink));
        PyStructSequence_SET_ITEM(v, 4, PyInt_FromLong((long)st->st_uid));
        PyStructSequence_SET_ITEM(v, 5, PyInt_FromLong((long)st->st_gid));
#ifdef HAVE_LARGEFILE_SUPPORT
        PyStructSequence_SET_ITEM(v, 6,
                                  PyLong_FromLongLong((PY_LONG_LONG)st->st_size));
#else
        PyStructSequence_SET_ITEM(v, 6, PyInt_FromLong(st->st_size));
#endif

#if defined(HAVE_STAT_TV_NSEC)
        ansec = st->st_atim.tv_nsec;
        mnsec = st->st_mtim.tv_nsec;
        cnsec = st->st_ctim.tv_nsec;
#elif defined(HAVE_STAT_TV_NSEC2)
        ansec = st->st_atimespec.tv_nsec;
        mnsec = st->st_mtimespec.tv_nsec;
        cnsec = st->st_ctimespec.tv_nsec;
#elif defined(HAVE_STAT_NSEC)
        ansec = st->st_atime_nsec;
        mnsec = st->st_mtime_nsec;
        cnsec = st->st_ctime_nsec;
#else
        ansec = mnsec = cnsec = 0;
#endif
        fill_time(v, 7, st->st_atime, ansec);
        fill_time(v, 8, st->st_mtime, mnsec);
        fill_time(v, 9, st->st_ctime, cnsec);

#ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
        PyStructSequence_SET_ITEM(v, ST_BLKSIZE_IDX,
                         PyInt_FromLong((long)st->st_blksize));
#endif
#ifdef HAVE_STRUCT_STAT_ST_BLOCKS
        PyStructSequence_SET_ITEM(v, ST_BLOCKS_IDX,
                         PyInt_FromLong((long)st->st_blocks));
#endif
#ifdef HAVE_STRUCT_STAT_ST_RDEV
        PyStructSequence_SET_ITEM(v, ST_RDEV_IDX,
                         PyInt_FromLong((long)st->st_rdev));
#endif
#ifdef HAVE_STRUCT_STAT_ST_GEN
        PyStructSequence_SET_ITEM(v, ST_GEN_IDX,
                         PyInt_FromLong((long)st->st_gen));
#endif
#ifdef HAVE_STRUCT_STAT_ST_BIRTHTIME
        {
          PyObject *val;
          unsigned long bsec,bnsec;
          bsec = (long)st->st_birthtime;
#ifdef HAVE_STAT_TV_NSEC2
          bnsec = st->st_birthtimespec.tv_nsec;
#else
          bnsec = 0;
#endif
          if (_stat_float_times) {
            val = PyFloat_FromDouble(bsec + 1e-9*bnsec);
          } else {
            val = PyInt_FromLong((long)bsec);
          }
          PyStructSequence_SET_ITEM(v, ST_BIRTHTIME_IDX,
                                    val);
        }
#endif
#ifdef HAVE_STRUCT_STAT_ST_FLAGS
        PyStructSequence_SET_ITEM(v, ST_FLAGS_IDX,
                         PyInt_FromLong((long)st->st_flags));
#endif

        if (PyErr_Occurred()) {
                Py_DECREF(v);
                return NULL;
        }

        return v;
}

#ifdef MS_WINDOWS

/* IsUNCRoot -- test whether the supplied path is of the form \\SERVER\SHARE\,
   where / can be used in place of \ and the trailing slash is optional.
   Both SERVER and SHARE must have at least one character.
*/

#define ISSLASHA(c) ((c) == '\\' || (c) == '/')
#define ISSLASHW(c) ((c) == L'\\' || (c) == L'/')
#ifndef ARRAYSIZE
#define ARRAYSIZE(a) (sizeof(a) / sizeof(a[0]))
#endif

static BOOL
IsUNCRootA(char *path, int pathlen)
{
        #define ISSLASH ISSLASHA

        int i, share;

        if (pathlen < 5 || !ISSLASH(path[0]) || !ISSLASH(path[1]))
                /* minimum UNCRoot is \\x\y */
                return FALSE;
        for (i = 2; i < pathlen ; i++)
                if (ISSLASH(path[i])) break;
        if (i == 2 || i == pathlen)
                /* do not allow \\\SHARE or \\SERVER */
                return FALSE;
        share = i+1;
        for (i = share; i < pathlen; i++)
                if (ISSLASH(path[i])) break;
        return (i != share && (i == pathlen || i == pathlen-1));

        #undef ISSLASH
}

#ifdef Py_WIN_WIDE_FILENAMES
static BOOL
IsUNCRootW(Py_UNICODE *path, int pathlen)
{
        #define ISSLASH ISSLASHW

        int i, share;

        if (pathlen < 5 || !ISSLASH(path[0]) || !ISSLASH(path[1]))
                /* minimum UNCRoot is \\x\y */
                return FALSE;
        for (i = 2; i < pathlen ; i++)
                if (ISSLASH(path[i])) break;
        if (i == 2 || i == pathlen)
                /* do not allow \\\SHARE or \\SERVER */
                return FALSE;
        share = i+1;
        for (i = share; i < pathlen; i++)
                if (ISSLASH(path[i])) break;
        return (i != share && (i == pathlen || i == pathlen-1));

        #undef ISSLASH
}
#endif /* Py_WIN_WIDE_FILENAMES */
#endif /* MS_WINDOWS */

static PyObject *
posix_do_stat(PyObject *self, PyObject *args,
              char *format,
#ifdef __VMS
              int (*statfunc)(const char *, STRUCT_STAT *, ...),
#else
              int (*statfunc)(const char *, STRUCT_STAT *),
#endif
              char *wformat,
              int (*wstatfunc)(const Py_UNICODE *, STRUCT_STAT *))
{
        STRUCT_STAT st;
        char *path = NULL;      /* pass this to stat; do not free() it */
        char *pathfree = NULL;  /* this memory must be free'd */
        int res;
        PyObject *result;

#ifdef Py_WIN_WIDE_FILENAMES
        /* If on wide-character-capable OS see if argument
           is Unicode and if so use wide API.  */
        if (unicode_file_names()) {
                PyUnicodeObject *po;
                if (PyArg_ParseTuple(args, wformat, &po)) {
                        Py_UNICODE *wpath = PyUnicode_AS_UNICODE(po);

                        Py_BEGIN_ALLOW_THREADS
                                /* PyUnicode_AS_UNICODE result OK without
                                   thread lock as it is a simple dereference. */
                        res = wstatfunc(wpath, &st);
                        Py_END_ALLOW_THREADS

                        if (res != 0)
                                return win32_error_unicode("stat", wpath);
                        return _pystat_fromstructstat(&st);
                }
                /* Drop the argument parsing error as narrow strings
                   are also valid. */
                PyErr_Clear();
        }
#endif

        if (!PyArg_ParseTuple(args, format,
                              Py_FileSystemDefaultEncoding, &path))
                return NULL;
        pathfree = path;

        Py_BEGIN_ALLOW_THREADS
        res = (*statfunc)(path, &st);
        Py_END_ALLOW_THREADS

        if (res != 0) {
#ifdef MS_WINDOWS
                result = win32_error("stat", pathfree);
#else
                result = posix_error_with_filename(pathfree);
#endif
        } 
        else
                result = _pystat_fromstructstat(&st);

        PyMem_Free(pathfree);
        return result;
}

/* POSIX methods */

PyDoc_STRVAR(posix_access__doc__,
"access(path, mode) -> 1 if granted, 0 otherwise\n\n\
Use the real uid/gid to test for access to a path.  Note that most\n\
operations will use the effective uid/gid, therefore this routine can\n\
be used in a suid/sgid environment to test if the invoking user has the\n\
specified access to the path.  The mode argument can be F_OK to test\n\
existence, or the inclusive-OR of R_OK, W_OK, and X_OK.");

static PyObject *
posix_access(PyObject *self, PyObject *args)
{
        char *path;
        int mode;
        
#ifdef Py_WIN_WIDE_FILENAMES
        DWORD attr;
        if (unicode_file_names()) {
                PyUnicodeObject *po;
                if (PyArg_ParseTuple(args, "Ui:access", &po, &mode)) {
                        Py_BEGIN_ALLOW_THREADS
                        /* PyUnicode_AS_UNICODE OK without thread lock as
                           it is a simple dereference. */
                        attr = GetFileAttributesW(PyUnicode_AS_UNICODE(po));
                        Py_END_ALLOW_THREADS
                        goto finish;
                }
                /* Drop the argument parsing error as narrow strings
                   are also valid. */
                PyErr_Clear();
        }
        if (!PyArg_ParseTuple(args, "eti:access",
                              Py_FileSystemDefaultEncoding, &path, &mode))
                return 0;
        Py_BEGIN_ALLOW_THREADS
        attr = GetFileAttributesA(path);
        Py_END_ALLOW_THREADS
        PyMem_Free(path);
finish:
        if (attr == 0xFFFFFFFF)
                /* File does not exist, or cannot read attributes */
                return PyBool_FromLong(0);
        /* Access is possible if either write access wasn't requested, or
           the file isn't read-only. */
        return PyBool_FromLong(!(mode & 2) || !(attr & FILE_ATTRIBUTE_READONLY));
#else
        int res;
        if (!PyArg_ParseTuple(args, "eti:access", 
                              Py_FileSystemDefaultEncoding, &path, &mode))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        res = access(path, mode);
        Py_END_ALLOW_THREADS
        PyMem_Free(path);
        return PyBool_FromLong(res == 0);
#endif
}

#ifndef F_OK
#define F_OK 0
#endif
#ifndef R_OK
#define R_OK 4
#endif
#ifndef W_OK
#define W_OK 2
#endif
#ifndef X_OK
#define X_OK 1
#endif

#ifdef HAVE_TTYNAME
PyDoc_STRVAR(posix_ttyname__doc__,
"ttyname(fd) -> string\n\n\
Return the name of the terminal device connected to 'fd'.");

static PyObject *
posix_ttyname(PyObject *self, PyObject *args)
{
        int id;
        char *ret;

        if (!PyArg_ParseTuple(args, "i:ttyname", &id))
                return NULL;

#if defined(__VMS)
        /* file descriptor 0 only, the default input device (stdin) */
        if (id == 0) {
                ret = ttyname();
        }
        else {
                ret = NULL;
        }
#else
        ret = ttyname(id);
#endif
        if (ret == NULL)
                return posix_error();
        return PyString_FromString(ret);
}
#endif

#ifdef HAVE_CTERMID
PyDoc_STRVAR(posix_ctermid__doc__,
"ctermid() -> string\n\n\
Return the name of the controlling terminal for this process.");

static PyObject *
posix_ctermid(PyObject *self, PyObject *noargs)
{
        char *ret;
        char buffer[L_ctermid];

#ifdef USE_CTERMID_R
        ret = ctermid_r(buffer);
#else
        ret = ctermid(buffer);
#endif
        if (ret == NULL)
                return posix_error();
        return PyString_FromString(buffer);
}
#endif

PyDoc_STRVAR(posix_chdir__doc__,
"chdir(path)\n\n\
Change the current working directory to the specified path.");

static PyObject *
posix_chdir(PyObject *self, PyObject *args)
{
#ifdef MS_WINDOWS
        return win32_1str(args, "chdir", "s:chdir", win32_chdir, "U:chdir", win32_wchdir);
#elif defined(PYOS_OS2) && defined(PYCC_GCC)
        return posix_1str(args, "et:chdir", _chdir2);
#elif defined(__VMS)
        return posix_1str(args, "et:chdir", (int (*)(const char *))chdir);
#else
        return posix_1str(args, "et:chdir", chdir);
#endif
}

#ifdef HAVE_FCHDIR
PyDoc_STRVAR(posix_fchdir__doc__,
"fchdir(fildes)\n\n\
Change to the directory of the given file descriptor.  fildes must be\n\
opened on a directory, not a file.");

static PyObject *
posix_fchdir(PyObject *self, PyObject *fdobj)
{
        return posix_fildes(fdobj, fchdir);
}
#endif /* HAVE_FCHDIR */


PyDoc_STRVAR(posix_chmod__doc__,
"chmod(path, mode)\n\n\
Change the access permissions of a file.");

static PyObject *
posix_chmod(PyObject *self, PyObject *args)
{
        char *path = NULL;
        int i;
        int res;
#ifdef Py_WIN_WIDE_FILENAMES
        DWORD attr;
        if (unicode_file_names()) {
                PyUnicodeObject *po;
                if (PyArg_ParseTuple(args, "Ui|:chmod", &po, &i)) {
                        Py_BEGIN_ALLOW_THREADS
                        attr = GetFileAttributesW(PyUnicode_AS_UNICODE(po));
                        if (attr != 0xFFFFFFFF) {
                                if (i & _S_IWRITE)
                                        attr &= ~FILE_ATTRIBUTE_READONLY;
                                else
                                        attr |= FILE_ATTRIBUTE_READONLY;
                                res = SetFileAttributesW(PyUnicode_AS_UNICODE(po), attr);
                        }
                        else
                                res = 0;
                        Py_END_ALLOW_THREADS
                        if (!res)
                                return win32_error_unicode("chmod",
                                                PyUnicode_AS_UNICODE(po));
                        Py_INCREF(Py_None);
                        return Py_None;
                }
                /* Drop the argument parsing error as narrow strings
                   are also valid. */
                PyErr_Clear();
        }
        if (!PyArg_ParseTuple(args, "eti:chmod", Py_FileSystemDefaultEncoding,
                              &path, &i))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        attr = GetFileAttributesA(path);
        if (attr != 0xFFFFFFFF) {
                if (i & _S_IWRITE)
                        attr &= ~FILE_ATTRIBUTE_READONLY;
                else
                        attr |= FILE_ATTRIBUTE_READONLY;
                res = SetFileAttributesA(path, attr);
        }
        else
                res = 0;
        Py_END_ALLOW_THREADS
        if (!res) {
                win32_error("chmod", path);
                PyMem_Free(path);
                return NULL;
        }
        PyMem_Free(path);
        Py_INCREF(Py_None);
        return Py_None;
#else /* Py_WIN_WIDE_FILENAMES */
        if (!PyArg_ParseTuple(args, "eti:chmod", Py_FileSystemDefaultEncoding,
                              &path, &i))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        res = chmod(path, i);
        Py_END_ALLOW_THREADS
        if (res < 0)
                return posix_error_with_allocated_filename(path);
        PyMem_Free(path);
        Py_INCREF(Py_None);
        return Py_None;
#endif
}


#ifdef HAVE_CHROOT
PyDoc_STRVAR(posix_chroot__doc__,
"chroot(path)\n\n\
Change root directory to path.");

static PyObject *
posix_chroot(PyObject *self, PyObject *args)
{
        return posix_1str(args, "et:chroot", chroot);
}
#endif

#ifdef HAVE_FSYNC
PyDoc_STRVAR(posix_fsync__doc__,
"fsync(fildes)\n\n\
force write of file with filedescriptor to disk.");

static PyObject *
posix_fsync(PyObject *self, PyObject *fdobj)
{
       return posix_fildes(fdobj, fsync);
}
#endif /* HAVE_FSYNC */

#ifdef HAVE_FDATASYNC

#ifdef __hpux
extern int fdatasync(int); /* On HP-UX, in libc but not in unistd.h */
#endif

PyDoc_STRVAR(posix_fdatasync__doc__,
"fdatasync(fildes)\n\n\
force write of file with filedescriptor to disk.\n\
 does not force update of metadata.");

static PyObject *
posix_fdatasync(PyObject *self, PyObject *fdobj)
{
       return posix_fildes(fdobj, fdatasync);
}
#endif /* HAVE_FDATASYNC */


#ifdef HAVE_CHOWN
PyDoc_STRVAR(posix_chown__doc__,
"chown(path, uid, gid)\n\n\
Change the owner and group id of path to the numeric uid and gid.");

static PyObject *
posix_chown(PyObject *self, PyObject *args)
{
        char *path = NULL;
        int uid, gid;
        int res;
        if (!PyArg_ParseTuple(args, "etii:chown",
                              Py_FileSystemDefaultEncoding, &path,
                              &uid, &gid))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        res = chown(path, (uid_t) uid, (gid_t) gid);
        Py_END_ALLOW_THREADS
        if (res < 0)
                return posix_error_with_allocated_filename(path);
        PyMem_Free(path);
        Py_INCREF(Py_None);
        return Py_None;
}
#endif /* HAVE_CHOWN */

#ifdef HAVE_LCHOWN
PyDoc_STRVAR(posix_lchown__doc__,
"lchown(path, uid, gid)\n\n\
Change the owner and group id of path to the numeric uid and gid.\n\
This function will not follow symbolic links.");

static PyObject *
posix_lchown(PyObject *self, PyObject *args)
{
        char *path = NULL;
        int uid, gid;
        int res;
        if (!PyArg_ParseTuple(args, "etii:lchown",
                              Py_FileSystemDefaultEncoding, &path,
                              &uid, &gid))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        res = lchown(path, (uid_t) uid, (gid_t) gid);
        Py_END_ALLOW_THREADS
        if (res < 0)
                return posix_error_with_allocated_filename(path);
        PyMem_Free(path);
        Py_INCREF(Py_None);
        return Py_None;
}
#endif /* HAVE_LCHOWN */


#ifdef HAVE_GETCWD
PyDoc_STRVAR(posix_getcwd__doc__,
"getcwd() -> path\n\n\
Return a string representing the current working directory.");

static PyObject *
posix_getcwd(PyObject *self, PyObject *noargs)
{
        char buf[1026];
        char *res;

        Py_BEGIN_ALLOW_THREADS
#if defined(PYOS_OS2) && defined(PYCC_GCC)
        res = _getcwd2(buf, sizeof buf);
#else
        res = getcwd(buf, sizeof buf);
#endif
        Py_END_ALLOW_THREADS
        if (res == NULL)
                return posix_error();
        return PyString_FromString(buf);
}

#ifdef Py_USING_UNICODE
PyDoc_STRVAR(posix_getcwdu__doc__,
"getcwdu() -> path\n\n\
Return a unicode string representing the current working directory.");

static PyObject *
posix_getcwdu(PyObject *self, PyObject *noargs)
{
        char buf[1026];
        char *res;

#ifdef Py_WIN_WIDE_FILENAMES
        DWORD len;
        if (unicode_file_names()) {
                wchar_t wbuf[1026];
                wchar_t *wbuf2 = wbuf;
                PyObject *resobj;
                Py_BEGIN_ALLOW_THREADS
                len = GetCurrentDirectoryW(sizeof wbuf/ sizeof wbuf[0], wbuf);
                /* If the buffer is large enough, len does not include the
                   terminating \0. If the buffer is too small, len includes
                   the space needed for the terminator. */
                if (len >= sizeof wbuf/ sizeof wbuf[0]) {
                        wbuf2 = malloc(len * sizeof(wchar_t));
                        if (wbuf2)
                                len = GetCurrentDirectoryW(len, wbuf2);
                }
                Py_END_ALLOW_THREADS
                if (!wbuf2) {
                        PyErr_NoMemory();
                        return NULL;
                }
                if (!len) {
                        if (wbuf2 != wbuf) free(wbuf2);
                        return win32_error("getcwdu", NULL);
                }
                resobj = PyUnicode_FromWideChar(wbuf2, len);
                if (wbuf2 != wbuf) free(wbuf2);
                return resobj;
        }
#endif

        Py_BEGIN_ALLOW_THREADS
#if defined(PYOS_OS2) && defined(PYCC_GCC)
        res = _getcwd2(buf, sizeof buf);
#else
        res = getcwd(buf, sizeof buf);
#endif
        Py_END_ALLOW_THREADS
        if (res == NULL)
                return posix_error();
        return PyUnicode_Decode(buf, strlen(buf), Py_FileSystemDefaultEncoding,"strict");
}
#endif
#endif


#ifdef HAVE_LINK
PyDoc_STRVAR(posix_link__doc__,
"link(src, dst)\n\n\
Create a hard link to a file.");

static PyObject *
posix_link(PyObject *self, PyObject *args)
{
        return posix_2str(args, "etet:link", link);
}
#endif /* HAVE_LINK */


PyDoc_STRVAR(posix_listdir__doc__,
"listdir(path) -> list_of_strings\n\n\
Return a list containing the names of the entries in the directory.\n\
\n\
        path: path of directory to list\n\
\n\
The list is in arbitrary order.  It does not include the special\n\
entries '.' and '..' even if they are present in the directory.");

static PyObject *
posix_listdir(PyObject *self, PyObject *args)
{
        /* XXX Should redo this putting the (now four) versions of opendir
           in separate files instead of having them all here... */
#if defined(MS_WINDOWS) && !defined(HAVE_OPENDIR)

        PyObject *d, *v;
        HANDLE hFindFile;
        BOOL result;
        WIN32_FIND_DATA FileData;
        char namebuf[MAX_PATH+5]; /* Overallocate for \\*.*\0 */
        char *bufptr = namebuf;
        Py_ssize_t len = sizeof(namebuf)-5; /* only claim to have space for MAX_PATH */

#ifdef Py_WIN_WIDE_FILENAMES
        /* If on wide-character-capable OS see if argument
           is Unicode and if so use wide API.  */
        if (unicode_file_names()) {
                PyObject *po;
                if (PyArg_ParseTuple(args, "U:listdir", &po)) {
                        WIN32_FIND_DATAW wFileData;
                        Py_UNICODE *wnamebuf;
                        Py_UNICODE wch;
                        /* Overallocate for \\*.*\0 */
                        len = PyUnicode_GET_SIZE(po);
                        wnamebuf = malloc((len + 5) * sizeof(wchar_t));
                        if (!wnamebuf) {
                                PyErr_NoMemory();
                                return NULL;
                        }
                        wcscpy(wnamebuf, PyUnicode_AS_UNICODE(po));
                        wch = len > 0 ? wnamebuf[len-1] : '\0';
                        if (wch != L'/' && wch != L'\\' && wch != L':')
                                wnamebuf[len++] = L'\\';
                        wcscpy(wnamebuf + len, L"*.*");
                        if ((d = PyList_New(0)) == NULL) {
                                free(wnamebuf);
                                return NULL;
                        }
                        hFindFile = FindFirstFileW(wnamebuf, &wFileData);
                        if (hFindFile == INVALID_HANDLE_VALUE) {
                                int error = GetLastError();
                                if (error == ERROR_FILE_NOT_FOUND) {
                                        free(wnamebuf);
                                        return d;
                                }
                                Py_DECREF(d);
                                win32_error_unicode("FindFirstFileW", wnamebuf);
                                free(wnamebuf);
                                return NULL;
                        }
                        do {
                                /* Skip over . and .. */
                                if (wcscmp(wFileData.cFileName, L".") != 0 &&
                                    wcscmp(wFileData.cFileName, L"..") != 0) {
                                        v = PyUnicode_FromUnicode(wFileData.cFileName, wcslen(wFileData.cFileName));
                                        if (v == NULL) {
                                                Py_DECREF(d);
                                                d = NULL;
                                                break;
                                        }
                                        if (PyList_Append(d, v) != 0) {
                                                Py_DECREF(v);
                                                Py_DECREF(d);
                                                d = NULL;
                                                break;
                                        }
                                        Py_DECREF(v);
                                }
                                Py_BEGIN_ALLOW_THREADS
                                result = FindNextFileW(hFindFile, &wFileData);
                                Py_END_ALLOW_THREADS
                                /* FindNextFile sets error to ERROR_NO_MORE_FILES if
                                   it got to the end of the directory. */
                                if (!result && GetLastError() != ERROR_NO_MORE_FILES) {
                                    Py_DECREF(d);
                                    win32_error_unicode("FindNextFileW", wnamebuf);
                                    FindClose(hFindFile);
                                    free(wnamebuf);
                                    return NULL;
                                }
                        } while (result == TRUE);

                        if (FindClose(hFindFile) == FALSE) {
                                Py_DECREF(d);
                                win32_error_unicode("FindClose", wnamebuf);
                                free(wnamebuf);
                                return NULL;
                        }
                        free(wnamebuf);
                        return d;
                }
                /* Drop the argument parsing error as narrow strings
                   are also valid. */
                PyErr_Clear();
        }
#endif

        if (!PyArg_ParseTuple(args, "et#:listdir",
                              Py_FileSystemDefaultEncoding, &bufptr, &len))
                return NULL;
        if (len > 0) {
                char ch = namebuf[len-1];
                if (ch != SEP && ch != ALTSEP && ch != ':')
                        namebuf[len++] = '/';
        }
        strcpy(namebuf + len, "*.*");

        if ((d = PyList_New(0)) == NULL)
                return NULL;

        hFindFile = FindFirstFile(namebuf, &FileData);
        if (hFindFile == INVALID_HANDLE_VALUE) {
                int error = GetLastError();
                if (error == ERROR_FILE_NOT_FOUND)
                        return d;
                Py_DECREF(d);
                return win32_error("FindFirstFile", namebuf);
        }
        do {
                /* Skip over . and .. */
                if (strcmp(FileData.cFileName, ".") != 0 &&
                    strcmp(FileData.cFileName, "..") != 0) {
                        v = PyString_FromString(FileData.cFileName);
                        if (v == NULL) {
                                Py_DECREF(d);
                                d = NULL;
                                break;
                        }
                        if (PyList_Append(d, v) != 0) {
                                Py_DECREF(v);
                                Py_DECREF(d);
                                d = NULL;
                                break;
                        }
                        Py_DECREF(v);
                }
                Py_BEGIN_ALLOW_THREADS
                result = FindNextFile(hFindFile, &FileData);
                Py_END_ALLOW_THREADS
                /* FindNextFile sets error to ERROR_NO_MORE_FILES if
                   it got to the end of the directory. */
                if (!result && GetLastError() != ERROR_NO_MORE_FILES) {
                    Py_DECREF(d);
                    win32_error("FindNextFile", namebuf);
                    FindClose(hFindFile);
                    return NULL;
                }
        } while (result == TRUE);

        if (FindClose(hFindFile) == FALSE) {
                Py_DECREF(d);
                return win32_error("FindClose", namebuf);
        }

        return d;

#elif defined(PYOS_OS2)

#ifndef MAX_PATH
#define MAX_PATH    CCHMAXPATH
#endif
    char *name, *pt;
    Py_ssize_t len;
    PyObject *d, *v;
    char namebuf[MAX_PATH+5];
    HDIR  hdir = 1;
    ULONG srchcnt = 1;
    FILEFINDBUF3   ep;
    APIRET rc;

    if (!PyArg_ParseTuple(args, "t#:listdir", &name, &len))
        return NULL;
    if (len >= MAX_PATH) {
                PyErr_SetString(PyExc_ValueError, "path too long");
        return NULL;
    }
    strcpy(namebuf, name);
    for (pt = namebuf; *pt; pt++)
        if (*pt == ALTSEP)
            *pt = SEP;
    if (namebuf[len-1] != SEP)
        namebuf[len++] = SEP;
    strcpy(namebuf + len, "*.*");

        if ((d = PyList_New(0)) == NULL)
        return NULL;

    rc = DosFindFirst(namebuf,         /* Wildcard Pattern to Match */
                      &hdir,           /* Handle to Use While Search Directory */
                      FILE_READONLY | FILE_HIDDEN | FILE_SYSTEM | FILE_DIRECTORY,
                      &ep, sizeof(ep), /* Structure to Receive Directory Entry */
                      &srchcnt,        /* Max and Actual Count of Entries Per Iteration */
                      FIL_STANDARD);   /* Format of Entry (EAs or Not) */

    if (rc != NO_ERROR) {
        errno = ENOENT;
        return posix_error_with_filename(name);
    }

    if (srchcnt > 0) { /* If Directory is NOT Totally Empty, */
        do {
            if (ep.achName[0] == '.'
            && (ep.achName[1] == '\0' || (ep.achName[1] == '.' && ep.achName[2] == '\0')))
                continue; /* Skip Over "." and ".." Names */

            strcpy(namebuf, ep.achName);

            /* Leave Case of Name Alone -- In Native Form */
            /* (Removed Forced Lowercasing Code) */

            v = PyString_FromString(namebuf);
            if (v == NULL) {
                Py_DECREF(d);
                d = NULL;
                break;
            }
            if (PyList_Append(d, v) != 0) {
                Py_DECREF(v);
                Py_DECREF(d);
                d = NULL;
                break;
            }
            Py_DECREF(v);
        } while (DosFindNext(hdir, &ep, sizeof(ep), &srchcnt) == NO_ERROR && srchcnt > 0);
    }

    return d;
#else

        char *name = NULL;
        PyObject *d, *v;
        DIR *dirp;
        struct dirent *ep;
        int arg_is_unicode = 1;

        errno = 0;
        if (!PyArg_ParseTuple(args, "U:listdir", &v)) {
                arg_is_unicode = 0;
                PyErr_Clear();
        }
        if (!PyArg_ParseTuple(args, "et:listdir", Py_FileSystemDefaultEncoding, &name))
                return NULL;
        if ((dirp = opendir(name)) == NULL) {
                return posix_error_with_allocated_filename(name);
        }
        if ((d = PyList_New(0)) == NULL) {
                closedir(dirp);
                PyMem_Free(name);
                return NULL;
        }
        for (;;) {
                Py_BEGIN_ALLOW_THREADS
                ep = readdir(dirp);
                Py_END_ALLOW_THREADS
                if (ep == NULL)
                        break;
                if (ep->d_name[0] == '.' &&
                    (NAMLEN(ep) == 1 ||
                     (ep->d_name[1] == '.' && NAMLEN(ep) == 2)))
                        continue;
                v = PyString_FromStringAndSize(ep->d_name, NAMLEN(ep));
                if (v == NULL) {
                        Py_DECREF(d);
                        d = NULL;
                        break;
                }
#ifdef Py_USING_UNICODE
                if (arg_is_unicode) {
                        PyObject *w;

                        w = PyUnicode_FromEncodedObject(v,
                                        Py_FileSystemDefaultEncoding,
                                        "strict");
                        if (w != NULL) {
                                Py_DECREF(v);
                                v = w;
                        }
                        else {
                                /* fall back to the original byte string, as
                                   discussed in patch #683592 */
                                PyErr_Clear();
                        }
                }
#endif
                if (PyList_Append(d, v) != 0) {
                        Py_DECREF(v);
                        Py_DECREF(d);
                        d = NULL;
                        break;
                }
                Py_DECREF(v);
        }
        if (errno != 0 && d != NULL) {
                /* readdir() returned NULL and set errno */
                closedir(dirp);
                Py_DECREF(d);
                return posix_error_with_allocated_filename(name); 
        }
        closedir(dirp);
        PyMem_Free(name);

        return d;

#endif /* which OS */
}  /* end of posix_listdir */

#ifdef MS_WINDOWS
/* A helper function for abspath on win32 */
static PyObject *
posix__getfullpathname(PyObject *self, PyObject *args)
{
        /* assume encoded strings wont more than double no of chars */
        char inbuf[MAX_PATH*2];
        char *inbufp = inbuf;
        Py_ssize_t insize = sizeof(inbuf);
        char outbuf[MAX_PATH*2];
        char *temp;
#ifdef Py_WIN_WIDE_FILENAMES
        if (unicode_file_names()) {
                PyUnicodeObject *po;
                if (PyArg_ParseTuple(args, "U|:_getfullpathname", &po)) {
                        Py_UNICODE woutbuf[MAX_PATH*2];
                        Py_UNICODE *wtemp;
                        if (!GetFullPathNameW(PyUnicode_AS_UNICODE(po),
                                                sizeof(woutbuf)/sizeof(woutbuf[0]),
                                                 woutbuf, &wtemp))
                                return win32_error("GetFullPathName", "");
                        return PyUnicode_FromUnicode(woutbuf, wcslen(woutbuf));
                }
                /* Drop the argument parsing error as narrow strings
                   are also valid. */
                PyErr_Clear();
        }
#endif
        if (!PyArg_ParseTuple (args, "et#:_getfullpathname",
                               Py_FileSystemDefaultEncoding, &inbufp,
                               &insize))
                return NULL;
        if (!GetFullPathName(inbuf, sizeof(outbuf)/sizeof(outbuf[0]),
                             outbuf, &temp))
                return win32_error("GetFullPathName", inbuf);
        if (PyUnicode_Check(PyTuple_GetItem(args, 0))) {
                return PyUnicode_Decode(outbuf, strlen(outbuf),
                        Py_FileSystemDefaultEncoding, NULL);
        }
        return PyString_FromString(outbuf);
} /* end of posix__getfullpathname */
#endif /* MS_WINDOWS */

PyDoc_STRVAR(posix_mkdir__doc__,
"mkdir(path [, mode=0777])\n\n\
Create a directory.");

static PyObject *
posix_mkdir(PyObject *self, PyObject *args)
{
        int res;
        char *path = NULL;
        int mode = 0777;

#ifdef Py_WIN_WIDE_FILENAMES
        if (unicode_file_names()) {
                PyUnicodeObject *po;
                if (PyArg_ParseTuple(args, "U|i:mkdir", &po, &mode)) {
                        Py_BEGIN_ALLOW_THREADS
                        /* PyUnicode_AS_UNICODE OK without thread lock as
                           it is a simple dereference. */
                        res = CreateDirectoryW(PyUnicode_AS_UNICODE(po), NULL);
                        Py_END_ALLOW_THREADS
                        if (!res)
                                return win32_error_unicode("mkdir", PyUnicode_AS_UNICODE(po));
                        Py_INCREF(Py_None);
                        return Py_None;
                }
                /* Drop the argument parsing error as narrow strings
                   are also valid. */
                PyErr_Clear();
        }
        if (!PyArg_ParseTuple(args, "et|i:mkdir",
                              Py_FileSystemDefaultEncoding, &path, &mode))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        /* PyUnicode_AS_UNICODE OK without thread lock as
           it is a simple dereference. */
        res = CreateDirectoryA(path, NULL);
        Py_END_ALLOW_THREADS
        if (!res) {
                win32_error("mkdir", path);
                PyMem_Free(path);
                return NULL;
        }
        PyMem_Free(path);
        Py_INCREF(Py_None);
        return Py_None;
#else

        if (!PyArg_ParseTuple(args, "et|i:mkdir",
                              Py_FileSystemDefaultEncoding, &path, &mode))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
#if ( defined(__WATCOMC__) || defined(PYCC_VACPP) ) && !defined(__QNX__)
        res = mkdir(path);
#else
        res = mkdir(path, mode);
#endif
        Py_END_ALLOW_THREADS
        if (res < 0)
                return posix_error_with_allocated_filename(path);
        PyMem_Free(path);
        Py_INCREF(Py_None);
        return Py_None;
#endif
}


/* sys/resource.h is needed for at least: wait3(), wait4(), broken nice. */
#if defined(HAVE_SYS_RESOURCE_H)
#include <sys/resource.h>
#endif


#ifdef HAVE_NICE
PyDoc_STRVAR(posix_nice__doc__,
"nice(inc) -> new_priority\n\n\
Decrease the priority of process by inc and return the new priority.");

static PyObject *
posix_nice(PyObject *self, PyObject *args)
{
        int increment, value;

        if (!PyArg_ParseTuple(args, "i:nice", &increment))
                return NULL;

        /* There are two flavours of 'nice': one that returns the new
           priority (as required by almost all standards out there) and the
           Linux/FreeBSD/BSDI one, which returns '0' on success and advices
           the use of getpriority() to get the new priority.

           If we are of the nice family that returns the new priority, we
           need to clear errno before the call, and check if errno is filled
           before calling posix_error() on a returnvalue of -1, because the
           -1 may be the actual new priority! */

        errno = 0;
        value = nice(increment);
#if defined(HAVE_BROKEN_NICE) && defined(HAVE_GETPRIORITY)
        if (value == 0)
                value = getpriority(PRIO_PROCESS, 0);
#endif
        if (value == -1 && errno != 0)
                /* either nice() or getpriority() returned an error */
                return posix_error();
        return PyInt_FromLong((long) value);
}
#endif /* HAVE_NICE */

PyDoc_STRVAR(posix_rename__doc__,
"rename(old, new)\n\n\
Rename a file or directory.");

static PyObject *
posix_rename(PyObject *self, PyObject *args)
{
#ifdef MS_WINDOWS
        PyObject *o1, *o2;
        char *p1, *p2;
        BOOL result;
        if (unicode_file_names()) {
            if (!PyArg_ParseTuple(args, "O&O&:rename", 
                convert_to_unicode, &o1,
                convert_to_unicode, &o2))
                    PyErr_Clear();
            else {
                    Py_BEGIN_ALLOW_THREADS
                    result = MoveFileW(PyUnicode_AsUnicode(o1),
                                       PyUnicode_AsUnicode(o2));
                    Py_END_ALLOW_THREADS
                    Py_DECREF(o1);
                    Py_DECREF(o2);
                    if (!result)
                            return win32_error("rename", NULL);
                    Py_INCREF(Py_None);
                    return Py_None;
            }
        }
        if (!PyArg_ParseTuple(args, "ss:rename", &p1, &p2))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        result = MoveFileA(p1, p2);
        Py_END_ALLOW_THREADS
        if (!result)
                return win32_error("rename", NULL);
        Py_INCREF(Py_None);
        return Py_None;
#else
        return posix_2str(args, "etet:rename", rename);
#endif
}


PyDoc_STRVAR(posix_rmdir__doc__,
"rmdir(path)\n\n\
Remove a directory.");

static PyObject *
posix_rmdir(PyObject *self, PyObject *args)
{
#ifdef MS_WINDOWS
        return win32_1str(args, "rmdir", "s:rmdir", RemoveDirectoryA, "U:rmdir", RemoveDirectoryW);
#else
        return posix_1str(args, "et:rmdir", rmdir);
#endif
}


PyDoc_STRVAR(posix_stat__doc__,
"stat(path) -> stat result\n\n\
Perform a stat system call on the given path.");

static PyObject *
posix_stat(PyObject *self, PyObject *args)
{
#ifdef MS_WINDOWS
        return posix_do_stat(self, args, "et:stat", STAT, "U:stat", win32_wstat);
#else
        return posix_do_stat(self, args, "et:stat", STAT, NULL, NULL);
#endif
}


#ifdef HAVE_SYSTEM
PyDoc_STRVAR(posix_system__doc__,
"system(command) -> exit_status\n\n\
Execute the command (a string) in a subshell.");

static PyObject *
posix_system(PyObject *self, PyObject *args)
{
        char *command;
        long sts;
        if (!PyArg_ParseTuple(args, "s:system", &command))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        sts = system(command);
        Py_END_ALLOW_THREADS
        return PyInt_FromLong(sts);
}
#endif


PyDoc_STRVAR(posix_umask__doc__,
"umask(new_mask) -> old_mask\n\n\
Set the current numeric umask and return the previous umask.");

static PyObject *
posix_umask(PyObject *self, PyObject *args)
{
        int i;
        if (!PyArg_ParseTuple(args, "i:umask", &i))
                return NULL;
        i = (int)umask(i);
        if (i < 0)
                return posix_error();
        return PyInt_FromLong((long)i);
}


PyDoc_STRVAR(posix_unlink__doc__,
"unlink(path)\n\n\
Remove a file (same as remove(path)).");

PyDoc_STRVAR(posix_remove__doc__,
"remove(path)\n\n\
Remove a file (same as unlink(path)).");

static PyObject *
posix_unlink(PyObject *self, PyObject *args)
{
#ifdef MS_WINDOWS
        return win32_1str(args, "remove", "s:remove", DeleteFileA, "U:remove", DeleteFileW);
#else
        return posix_1str(args, "et:remove", unlink);
#endif
}


#ifdef HAVE_UNAME
PyDoc_STRVAR(posix_uname__doc__,
"uname() -> (sysname, nodename, release, version, machine)\n\n\
Return a tuple identifying the current operating system.");

static PyObject *
posix_uname(PyObject *self, PyObject *noargs)
{
        struct utsname u;
        int res;

        Py_BEGIN_ALLOW_THREADS
        res = uname(&u);
        Py_END_ALLOW_THREADS
        if (res < 0)
                return posix_error();
        return Py_BuildValue("(sssss)",
                             u.sysname,
                             u.nodename,
                             u.release,
                             u.version,
                             u.machine);
}
#endif /* HAVE_UNAME */

static int
extract_time(PyObject *t, long* sec, long* usec)
{
        long intval;
        if (PyFloat_Check(t)) {
                double tval = PyFloat_AsDouble(t);
                PyObject *intobj = t->ob_type->tp_as_number->nb_int(t);
                if (!intobj)
                        return -1;
                intval = PyInt_AsLong(intobj);
                Py_DECREF(intobj);
                if (intval == -1 && PyErr_Occurred())
                        return -1;
                *sec = intval;
                *usec = (long)((tval - intval) * 1e6); /* can't exceed 1000000 */
                if (*usec < 0)
                        /* If rounding gave us a negative number,
                           truncate.  */
                        *usec = 0;
                return 0;
        }
        intval = PyInt_AsLong(t);
        if (intval == -1 && PyErr_Occurred())
                return -1;
        *sec = intval;
        *usec = 0;
        return 0;
}

PyDoc_STRVAR(posix_utime__doc__,
"utime(path, (atime, mtime))\n\
utime(path, None)\n\n\
Set the access and modified time of the file to the given values.  If the\n\
second form is used, set the access and modified times to the current time.");

static PyObject *
posix_utime(PyObject *self, PyObject *args)
{
#ifdef Py_WIN_WIDE_FILENAMES
        PyObject *arg;
        PyUnicodeObject *obwpath;
        wchar_t *wpath = NULL;
        char *apath = NULL;
        HANDLE hFile;
        long atimesec, mtimesec, ausec, musec;
        FILETIME atime, mtime;
        PyObject *result = NULL;

        if (unicode_file_names()) {
                if (PyArg_ParseTuple(args, "UO|:utime", &obwpath, &arg)) {
                        wpath = PyUnicode_AS_UNICODE(obwpath);
                        Py_BEGIN_ALLOW_THREADS
                        hFile = CreateFileW(wpath, FILE_WRITE_ATTRIBUTES, 0,
                                            NULL, OPEN_EXISTING, 0, NULL);
                        Py_END_ALLOW_THREADS
                        if (hFile == INVALID_HANDLE_VALUE)
                                return win32_error_unicode("utime", wpath);
                } else
                        /* Drop the argument parsing error as narrow strings
                           are also valid. */
                        PyErr_Clear();
        }
        if (!wpath) {
                if (!PyArg_ParseTuple(args, "etO:utime",
                                Py_FileSystemDefaultEncoding, &apath, &arg))
                        return NULL;
                Py_BEGIN_ALLOW_THREADS
                hFile = CreateFileA(apath, FILE_WRITE_ATTRIBUTES, 0,
                                    NULL, OPEN_EXISTING, 0, NULL);
                Py_END_ALLOW_THREADS
                if (hFile == INVALID_HANDLE_VALUE) {
                        win32_error("utime", apath);
                        PyMem_Free(apath);
                        return NULL;
                }
                PyMem_Free(apath);
        }
        
        if (arg == Py_None) {
                SYSTEMTIME now;
                GetSystemTime(&now);
                if (!SystemTimeToFileTime(&now, &mtime) ||
                    !SystemTimeToFileTime(&now, &atime)) {
                        win32_error("utime", NULL);
                        goto done;
                    }
        }
        else if (!PyTuple_Check(arg) || PyTuple_Size(arg) != 2) {
                PyErr_SetString(PyExc_TypeError,
                                "utime() arg 2 must be a tuple (atime, mtime)");
                goto done;
        }
        else {
                if (extract_time(PyTuple_GET_ITEM(arg, 0),
                                 &atimesec, &ausec) == -1)
                        goto done;
                time_t_to_FILE_TIME(atimesec, ausec, &atime);
                if (extract_time(PyTuple_GET_ITEM(arg, 1),
                                 &mtimesec, &musec) == -1)
                        goto done;
                time_t_to_FILE_TIME(mtimesec, musec, &mtime);
        }
        if (!SetFileTime(hFile, NULL, &atime, &mtime)) {
                /* Avoid putting the file name into the error here,
                   as that may confuse the user into believing that
                   something is wrong with the file, when it also
                   could be the time stamp that gives a problem. */
                win32_error("utime", NULL);
        }
        Py_INCREF(Py_None);
        result = Py_None;
done:
        CloseHandle(hFile);
        return result;
#else /* Py_WIN_WIDE_FILENAMES */

        char *path = NULL;
        long atime, mtime, ausec, musec;
        int res;
        PyObject* arg;

#if defined(HAVE_UTIMES)
        struct timeval buf[2];
#define ATIME buf[0].tv_sec
#define MTIME buf[1].tv_sec
#elif defined(HAVE_UTIME_H)
/* XXX should define struct utimbuf instead, above */
        struct utimbuf buf;
#define ATIME buf.actime
#define MTIME buf.modtime
#define UTIME_ARG &buf
#else /* HAVE_UTIMES */
        time_t buf[2];
#define ATIME buf[0]
#define MTIME buf[1]
#define UTIME_ARG buf
#endif /* HAVE_UTIMES */


        if (!PyArg_ParseTuple(args, "etO:utime",
                                  Py_FileSystemDefaultEncoding, &path, &arg))
                return NULL;
        if (arg == Py_None) {
                /* optional time values not given */
                Py_BEGIN_ALLOW_THREADS
                res = utime(path, NULL);
                Py_END_ALLOW_THREADS
        }
        else if (!PyTuple_Check(arg) || PyTuple_Size(arg) != 2) {
                PyErr_SetString(PyExc_TypeError,
                                "utime() arg 2 must be a tuple (atime, mtime)");
                PyMem_Free(path);
                return NULL;
        }
        else {
                if (extract_time(PyTuple_GET_ITEM(arg, 0),
                                 &atime, &ausec) == -1) {
                        PyMem_Free(path);
                        return NULL;
                }
                if (extract_time(PyTuple_GET_ITEM(arg, 1),
                                 &mtime, &musec) == -1) {
                        PyMem_Free(path);
                        return NULL;
                }
                ATIME = atime;
                MTIME = mtime;
#ifdef HAVE_UTIMES
                buf[0].tv_usec = ausec;
                buf[1].tv_usec = musec;
                Py_BEGIN_ALLOW_THREADS
                res = utimes(path, buf);
                Py_END_ALLOW_THREADS
#else
                Py_BEGIN_ALLOW_THREADS
                res = utime(path, UTIME_ARG);
                Py_END_ALLOW_THREADS
#endif /* HAVE_UTIMES */
        }
        if (res < 0) {
                return posix_error_with_allocated_filename(path);
        }
        PyMem_Free(path);
        Py_INCREF(Py_None);
        return Py_None;
#undef UTIME_ARG
#undef ATIME
#undef MTIME
#endif /* Py_WIN_WIDE_FILENAMES */
}


/* Process operations */

PyDoc_STRVAR(posix__exit__doc__,
"_exit(status)\n\n\
Exit to the system with specified status, without normal exit processing.");

static PyObject *
posix__exit(PyObject *self, PyObject *args)
{
        int sts;
        if (!PyArg_ParseTuple(args, "i:_exit", &sts))
                return NULL;
        _exit(sts);
        return NULL; /* Make gcc -Wall happy */
}

#if defined(HAVE_EXECV) || defined(HAVE_SPAWNV)
static void
free_string_array(char **array, Py_ssize_t count)
{
        Py_ssize_t i;
        for (i = 0; i < count; i++)
                PyMem_Free(array[i]);
        PyMem_DEL(array);
}
#endif


#ifdef HAVE_EXECV
PyDoc_STRVAR(posix_execv__doc__,
"execv(path, args)\n\n\
Execute an executable path with arguments, replacing current process.\n\
\n\
        path: path of executable file\n\
        args: tuple or list of strings");

static PyObject *
posix_execv(PyObject *self, PyObject *args)
{
        char *path;
        PyObject *argv;
        char **argvlist;
        Py_ssize_t i, argc;
        PyObject *(*getitem)(PyObject *, Py_ssize_t);

        /* execv has two arguments: (path, argv), where
           argv is a list or tuple of strings. */

        if (!PyArg_ParseTuple(args, "etO:execv",
                              Py_FileSystemDefaultEncoding,
                              &path, &argv))
                return NULL;
        if (PyList_Check(argv)) {
                argc = PyList_Size(argv);
                getitem = PyList_GetItem;
        }
        else if (PyTuple_Check(argv)) {
                argc = PyTuple_Size(argv);
                getitem = PyTuple_GetItem;
        }
        else {
                PyErr_SetString(PyExc_TypeError, "execv() arg 2 must be a tuple or list");
                PyMem_Free(path);
                return NULL;
        }

        argvlist = PyMem_NEW(char *, argc+1);
        if (argvlist == NULL) {
                PyMem_Free(path);
                return PyErr_NoMemory();
        }
        for (i = 0; i < argc; i++) {
                if (!PyArg_Parse((*getitem)(argv, i), "et",
                                 Py_FileSystemDefaultEncoding,
                                 &argvlist[i])) {
                        free_string_array(argvlist, i);
                        PyErr_SetString(PyExc_TypeError,
                                        "execv() arg 2 must contain only strings");
                        PyMem_Free(path);
                        return NULL;

                }
        }
        argvlist[argc] = NULL;

        execv(path, argvlist);

        /* If we get here it's definitely an error */

        free_string_array(argvlist, argc);
        PyMem_Free(path);
        return posix_error();
}


PyDoc_STRVAR(posix_execve__doc__,
"execve(path, args, env)\n\n\
Execute a path with arguments and environment, replacing current process.\n\
\n\
        path: path of executable file\n\
        args: tuple or list of arguments\n\
        env: dictionary of strings mapping to strings");

static PyObject *
posix_execve(PyObject *self, PyObject *args)
{
        char *path;
        PyObject *argv, *env;
        char **argvlist;
        char **envlist;
        PyObject *key, *val, *keys=NULL, *vals=NULL;
        Py_ssize_t i, pos, argc, envc;
        PyObject *(*getitem)(PyObject *, Py_ssize_t);
        Py_ssize_t lastarg = 0;

        /* execve has three arguments: (path, argv, env), where
           argv is a list or tuple of strings and env is a dictionary
           like posix.environ. */

        if (!PyArg_ParseTuple(args, "etOO:execve",
                              Py_FileSystemDefaultEncoding,
                              &path, &argv, &env))
                return NULL;
        if (PyList_Check(argv)) {
                argc = PyList_Size(argv);
                getitem = PyList_GetItem;
        }
        else if (PyTuple_Check(argv)) {
                argc = PyTuple_Size(argv);
                getitem = PyTuple_GetItem;
        }
        else {
                PyErr_SetString(PyExc_TypeError,
                                "execve() arg 2 must be a tuple or list");
                goto fail_0;
        }
        if (!PyMapping_Check(env)) {
                PyErr_SetString(PyExc_TypeError,
                                "execve() arg 3 must be a mapping object");
                goto fail_0;
        }

        argvlist = PyMem_NEW(char *, argc+1);
        if (argvlist == NULL) {
                PyErr_NoMemory();
                goto fail_0;
        }
        for (i = 0; i < argc; i++) {
                if (!PyArg_Parse((*getitem)(argv, i),
                                 "et;execve() arg 2 must contain only strings",
                                 Py_FileSystemDefaultEncoding,
                                 &argvlist[i]))
                {
                        lastarg = i;
                        goto fail_1;
                }
        }
        lastarg = argc;
        argvlist[argc] = NULL;

        i = PyMapping_Size(env);
        if (i < 0)
                goto fail_1;
        envlist = PyMem_NEW(char *, i + 1);
        if (envlist == NULL) {
                PyErr_NoMemory();
                goto fail_1;
        }
        envc = 0;
        keys = PyMapping_Keys(env);
        vals = PyMapping_Values(env);
        if (!keys || !vals)
                goto fail_2;
        if (!PyList_Check(keys) || !PyList_Check(vals)) {
                PyErr_SetString(PyExc_TypeError,
                        "execve(): env.keys() or env.values() is not a list");
                goto fail_2;
        }

        for (pos = 0; pos < i; pos++) {
                char *p, *k, *v;
                size_t len;

                key = PyList_GetItem(keys, pos);
                val = PyList_GetItem(vals, pos);
                if (!key || !val)
                        goto fail_2;

                if (!PyArg_Parse(
                            key,
                            "s;execve() arg 3 contains a non-string key",
                            &k) ||
                    !PyArg_Parse(
                            val,
                            "s;execve() arg 3 contains a non-string value",
                            &v))
                {
                        goto fail_2;
                }

#if defined(PYOS_OS2)
        /* Omit Pseudo-Env Vars that Would Confuse Programs if Passed On */
        if (stricmp(k, "BEGINLIBPATH") != 0 && stricmp(k, "ENDLIBPATH") != 0) {
#endif
                len = PyString_Size(key) + PyString_Size(val) + 2;
                p = PyMem_NEW(char, len);
                if (p == NULL) {
                        PyErr_NoMemory();
                        goto fail_2;
                }
                PyOS_snprintf(p, len, "%s=%s", k, v);
                envlist[envc++] = p;
#if defined(PYOS_OS2)
    }
#endif
        }
        envlist[envc] = 0;

        execve(path, argvlist, envlist);

        /* If we get here it's definitely an error */

        (void) posix_error();

  fail_2:
        while (--envc >= 0)
                PyMem_DEL(envlist[envc]);
        PyMem_DEL(envlist);
  fail_1:
        free_string_array(argvlist, lastarg);
        Py_XDECREF(vals);
        Py_XDECREF(keys);
  fail_0:
        PyMem_Free(path);
        return NULL;
}
#endif /* HAVE_EXECV */


#ifdef HAVE_SPAWNV
PyDoc_STRVAR(posix_spawnv__doc__,
"spawnv(mode, path, args)\n\n\
Execute the program 'path' in a new process.\n\
\n\
        mode: mode of process creation\n\
        path: path of executable file\n\
        args: tuple or list of strings");

static PyObject *
posix_spawnv(PyObject *self, PyObject *args)
{
        char *path;
        PyObject *argv;
        char **argvlist;
        int mode, i;
        Py_ssize_t argc;
        Py_intptr_t spawnval;
        PyObject *(*getitem)(PyObject *, Py_ssize_t);

        /* spawnv has three arguments: (mode, path, argv), where
           argv is a list or tuple of strings. */

        if (!PyArg_ParseTuple(args, "ietO:spawnv", &mode,
                              Py_FileSystemDefaultEncoding,
                              &path, &argv))
                return NULL;
        if (PyList_Check(argv)) {
                argc = PyList_Size(argv);
                getitem = PyList_GetItem;
        }
        else if (PyTuple_Check(argv)) {
                argc = PyTuple_Size(argv);
                getitem = PyTuple_GetItem;
        }
        else {
                PyErr_SetString(PyExc_TypeError,
                                "spawnv() arg 2 must be a tuple or list");
                PyMem_Free(path);
                return NULL;
        }

        argvlist = PyMem_NEW(char *, argc+1);
        if (argvlist == NULL) {
                PyMem_Free(path);
                return PyErr_NoMemory();
        }
        for (i = 0; i < argc; i++) {
                if (!PyArg_Parse((*getitem)(argv, i), "et",
                                 Py_FileSystemDefaultEncoding,
                                 &argvlist[i])) {
                        free_string_array(argvlist, i);
                        PyErr_SetString(
                                PyExc_TypeError,
                                "spawnv() arg 2 must contain only strings");
                        PyMem_Free(path);
                        return NULL;
                }
        }
        argvlist[argc] = NULL;

#if defined(PYOS_OS2) && defined(PYCC_GCC)
        Py_BEGIN_ALLOW_THREADS
        spawnval = spawnv(mode, path, argvlist);
        Py_END_ALLOW_THREADS
#else
        if (mode == _OLD_P_OVERLAY)
                mode = _P_OVERLAY;

        Py_BEGIN_ALLOW_THREADS
        spawnval = _spawnv(mode, path, argvlist);
        Py_END_ALLOW_THREADS
#endif

        free_string_array(argvlist, argc);
        PyMem_Free(path);

        if (spawnval == -1)
                return posix_error();
        else
#if SIZEOF_LONG == SIZEOF_VOID_P
                return Py_BuildValue("l", (long) spawnval);
#else
                return Py_BuildValue("L", (PY_LONG_LONG) spawnval);
#endif
}


PyDoc_STRVAR(posix_spawnve__doc__,
"spawnve(mode, path, args, env)\n\n\
Execute the program 'path' in a new process.\n\
\n\
        mode: mode of process creation\n\
        path: path of executable file\n\
        args: tuple or list of arguments\n\
        env: dictionary of strings mapping to strings");

static PyObject *
posix_spawnve(PyObject *self, PyObject *args)
{
        char *path;
        PyObject *argv, *env;
        char **argvlist;
        char **envlist;
        PyObject *key, *val, *keys=NULL, *vals=NULL, *res=NULL;
        int mode, pos, envc;
        Py_ssize_t argc, i;
        Py_intptr_t spawnval;
        PyObject *(*getitem)(PyObject *, Py_ssize_t);
        Py_ssize_t lastarg = 0;

        /* spawnve has four arguments: (mode, path, argv, env), where
           argv is a list or tuple of strings and env is a dictionary
           like posix.environ. */

        if (!PyArg_ParseTuple(args, "ietOO:spawnve", &mode,
                              Py_FileSystemDefaultEncoding,
                              &path, &argv, &env))
                return NULL;
        if (PyList_Check(argv)) {
                argc = PyList_Size(argv);
                getitem = PyList_GetItem;
        }
        else if (PyTuple_Check(argv)) {
                argc = PyTuple_Size(argv);
                getitem = PyTuple_GetItem;
        }
        else {
                PyErr_SetString(PyExc_TypeError,
                                "spawnve() arg 2 must be a tuple or list");
                goto fail_0;
        }
        if (!PyMapping_Check(env)) {
                PyErr_SetString(PyExc_TypeError,
                                "spawnve() arg 3 must be a mapping object");
                goto fail_0;
        }

        argvlist = PyMem_NEW(char *, argc+1);
        if (argvlist == NULL) {
                PyErr_NoMemory();
                goto fail_0;
        }
        for (i = 0; i < argc; i++) {
                if (!PyArg_Parse((*getitem)(argv, i),
                             "et;spawnve() arg 2 must contain only strings",
                                 Py_FileSystemDefaultEncoding,
                                 &argvlist[i]))
                {
                        lastarg = i;
                        goto fail_1;
                }
        }
        lastarg = argc;
        argvlist[argc] = NULL;

        i = PyMapping_Size(env);
        if (i < 0)
                goto fail_1;
        envlist = PyMem_NEW(char *, i + 1);
        if (envlist == NULL) {
                PyErr_NoMemory();
                goto fail_1;
        }
        envc = 0;
        keys = PyMapping_Keys(env);
        vals = PyMapping_Values(env);
        if (!keys || !vals)
                goto fail_2;
        if (!PyList_Check(keys) || !PyList_Check(vals)) {
                PyErr_SetString(PyExc_TypeError,
                        "spawnve(): env.keys() or env.values() is not a list");
                goto fail_2;
        }

        for (pos = 0; pos < i; pos++) {
                char *p, *k, *v;
                size_t len;

                key = PyList_GetItem(keys, pos);
                val = PyList_GetItem(vals, pos);
                if (!key || !val)
                        goto fail_2;

                if (!PyArg_Parse(
                            key,
                            "s;spawnve() arg 3 contains a non-string key",
                            &k) ||
                    !PyArg_Parse(
                            val,
                            "s;spawnve() arg 3 contains a non-string value",
                            &v))
                {
                        goto fail_2;
                }
                len = PyString_Size(key) + PyString_Size(val) + 2;
                p = PyMem_NEW(char, len);
                if (p == NULL) {
                        PyErr_NoMemory();
                        goto fail_2;
                }
                PyOS_snprintf(p, len, "%s=%s", k, v);
                envlist[envc++] = p;
        }
        envlist[envc] = 0;

#if defined(PYOS_OS2) && defined(PYCC_GCC)
        Py_BEGIN_ALLOW_THREADS
        spawnval = spawnve(mode, path, argvlist, envlist);
        Py_END_ALLOW_THREADS
#else
        if (mode == _OLD_P_OVERLAY)
                mode = _P_OVERLAY;

        Py_BEGIN_ALLOW_THREADS
        spawnval = _spawnve(mode, path, argvlist, envlist);
        Py_END_ALLOW_THREADS
#endif

        if (spawnval == -1)
                (void) posix_error();
        else
#if SIZEOF_LONG == SIZEOF_VOID_P
                res = Py_BuildValue("l", (long) spawnval);
#else
                res = Py_BuildValue("L", (PY_LONG_LONG) spawnval);
#endif

  fail_2:
        while (--envc >= 0)
                PyMem_DEL(envlist[envc]);
        PyMem_DEL(envlist);
  fail_1:
        free_string_array(argvlist, lastarg);
        Py_XDECREF(vals);
        Py_XDECREF(keys);
  fail_0:
        PyMem_Free(path);
        return res;
}

/* OS/2 supports spawnvp & spawnvpe natively */
#if defined(PYOS_OS2)
PyDoc_STRVAR(posix_spawnvp__doc__,
"spawnvp(mode, file, args)\n\n\
Execute the program 'file' in a new process, using the environment\n\
search path to find the file.\n\
\n\
        mode: mode of process creation\n\
        file: executable file name\n\
        args: tuple or list of strings");

static PyObject *
posix_spawnvp(PyObject *self, PyObject *args)
{
        char *path;
        PyObject *argv;
        char **argvlist;
        int mode, i, argc;
        Py_intptr_t spawnval;
        PyObject *(*getitem)(PyObject *, Py_ssize_t);

        /* spawnvp has three arguments: (mode, path, argv), where
           argv is a list or tuple of strings. */

        if (!PyArg_ParseTuple(args, "ietO:spawnvp", &mode,
                              Py_FileSystemDefaultEncoding,
                              &path, &argv))
                return NULL;
        if (PyList_Check(argv)) {
                argc = PyList_Size(argv);
                getitem = PyList_GetItem;
        }
        else if (PyTuple_Check(argv)) {
                argc = PyTuple_Size(argv);
                getitem = PyTuple_GetItem;
        }
        else {
                PyErr_SetString(PyExc_TypeError,
                                "spawnvp() arg 2 must be a tuple or list");
                PyMem_Free(path);
                return NULL;
        }

        argvlist = PyMem_NEW(char *, argc+1);
        if (argvlist == NULL) {
                PyMem_Free(path);
                return PyErr_NoMemory();
        }
        for (i = 0; i < argc; i++) {
                if (!PyArg_Parse((*getitem)(argv, i), "et",
                                 Py_FileSystemDefaultEncoding,
                                 &argvlist[i])) {
                        free_string_array(argvlist, i);
                        PyErr_SetString(
                                PyExc_TypeError,
                                "spawnvp() arg 2 must contain only strings");
                        PyMem_Free(path);
                        return NULL;
                }
        }
        argvlist[argc] = NULL;

        Py_BEGIN_ALLOW_THREADS
#if defined(PYCC_GCC)
        spawnval = spawnvp(mode, path, argvlist);
#else
        spawnval = _spawnvp(mode, path, argvlist);
#endif
        Py_END_ALLOW_THREADS

        free_string_array(argvlist, argc);
        PyMem_Free(path);

        if (spawnval == -1)
                return posix_error();
        else
                return Py_BuildValue("l", (long) spawnval);
}


PyDoc_STRVAR(posix_spawnvpe__doc__,
"spawnvpe(mode, file, args, env)\n\n\
Execute the program 'file' in a new process, using the environment\n\
search path to find the file.\n\
\n\
        mode: mode of process creation\n\
        file: executable file name\n\
        args: tuple or list of arguments\n\
        env: dictionary of strings mapping to strings");

static PyObject *
posix_spawnvpe(PyObject *self, PyObject *args)
{
        char *path;
        PyObject *argv, *env;
        char **argvlist;
        char **envlist;
        PyObject *key, *val, *keys=NULL, *vals=NULL, *res=NULL;
        int mode, i, pos, argc, envc;
        Py_intptr_t spawnval;
        PyObject *(*getitem)(PyObject *, Py_ssize_t);
        int lastarg = 0;

        /* spawnvpe has four arguments: (mode, path, argv, env), where
           argv is a list or tuple of strings and env is a dictionary
           like posix.environ. */

        if (!PyArg_ParseTuple(args, "ietOO:spawnvpe", &mode,
                              Py_FileSystemDefaultEncoding,
                              &path, &argv, &env))
                return NULL;
        if (PyList_Check(argv)) {
                argc = PyList_Size(argv);
                getitem = PyList_GetItem;
        }
        else if (PyTuple_Check(argv)) {
                argc = PyTuple_Size(argv);
                getitem = PyTuple_GetItem;
        }
        else {
                PyErr_SetString(PyExc_TypeError,
                                "spawnvpe() arg 2 must be a tuple or list");
                goto fail_0;
        }
        if (!PyMapping_Check(env)) {
                PyErr_SetString(PyExc_TypeError,
                                "spawnvpe() arg 3 must be a mapping object");
                goto fail_0;
        }

        argvlist = PyMem_NEW(char *, argc+1);
        if (argvlist == NULL) {
                PyErr_NoMemory();
                goto fail_0;
        }
        for (i = 0; i < argc; i++) {
                if (!PyArg_Parse((*getitem)(argv, i),
                             "et;spawnvpe() arg 2 must contain only strings",
                                 Py_FileSystemDefaultEncoding,
                                 &argvlist[i]))
                {
                        lastarg = i;
                        goto fail_1;
                }
        }
        lastarg = argc;
        argvlist[argc] = NULL;

        i = PyMapping_Size(env);
        if (i < 0)
                goto fail_1;
        envlist = PyMem_NEW(char *, i + 1);
        if (envlist == NULL) {
                PyErr_NoMemory();
                goto fail_1;
        }
        envc = 0;
        keys = PyMapping_Keys(env);
        vals = PyMapping_Values(env);
        if (!keys || !vals)
                goto fail_2;
        if (!PyList_Check(keys) || !PyList_Check(vals)) {
                PyErr_SetString(PyExc_TypeError,
                        "spawnvpe(): env.keys() or env.values() is not a list");
                goto fail_2;
        }

        for (pos = 0; pos < i; pos++) {
                char *p, *k, *v;
                size_t len;

                key = PyList_GetItem(keys, pos);
                val = PyList_GetItem(vals, pos);
                if (!key || !val)
                        goto fail_2;

                if (!PyArg_Parse(
                            key,
                            "s;spawnvpe() arg 3 contains a non-string key",
                            &k) ||
                    !PyArg_Parse(
                            val,
                            "s;spawnvpe() arg 3 contains a non-string value",
                            &v))
                {
                        goto fail_2;
                }
                len = PyString_Size(key) + PyString_Size(val) + 2;
                p = PyMem_NEW(char, len);
                if (p == NULL) {
                        PyErr_NoMemory();
                        goto fail_2;
                }
                PyOS_snprintf(p, len, "%s=%s", k, v);
                envlist[envc++] = p;
        }
        envlist[envc] = 0;

        Py_BEGIN_ALLOW_THREADS
#if defined(PYCC_GCC)
        spawnval = spawnve(mode, path, argvlist, envlist);
#else
        spawnval = _spawnve(mode, path, argvlist, envlist);
#endif
        Py_END_ALLOW_THREADS

        if (spawnval == -1)
                (void) posix_error();
        else
                res = Py_BuildValue("l", (long) spawnval);

  fail_2:
        while (--envc >= 0)
                PyMem_DEL(envlist[envc]);
        PyMem_DEL(envlist);
  fail_1:
        free_string_array(argvlist, lastarg);
        Py_XDECREF(vals);
        Py_XDECREF(keys);
  fail_0:
        PyMem_Free(path);
        return res;
}
#endif /* PYOS_OS2 */
#endif /* HAVE_SPAWNV */


#ifdef HAVE_FORK1
PyDoc_STRVAR(posix_fork1__doc__,
"fork1() -> pid\n\n\
Fork a child process with a single multiplexed (i.e., not bound) thread.\n\
\n\
Return 0 to child process and PID of child to parent process.");

static PyObject *
posix_fork1(PyObject *self, PyObject *noargs)
{
        int pid = fork1();
        if (pid == -1)
                return posix_error();
        PyOS_AfterFork();
        return PyInt_FromLong((long)pid);
}
#endif


#ifdef HAVE_FORK
PyDoc_STRVAR(posix_fork__doc__,
"fork() -> pid\n\n\
Fork a child process.\n\
Return 0 to child process and PID of child to parent process.");

static PyObject *
posix_fork(PyObject *self, PyObject *noargs)
{
        int pid = fork();
        if (pid == -1)
                return posix_error();
        if (pid == 0)
                PyOS_AfterFork();
        return PyInt_FromLong((long)pid);
}
#endif

/* AIX uses /dev/ptc but is otherwise the same as /dev/ptmx */
/* IRIX has both /dev/ptc and /dev/ptmx, use ptmx */
#if defined(HAVE_DEV_PTC) && !defined(HAVE_DEV_PTMX)
#define DEV_PTY_FILE "/dev/ptc"
#define HAVE_DEV_PTMX
#else
#define DEV_PTY_FILE "/dev/ptmx"
#endif

#if defined(HAVE_OPENPTY) || defined(HAVE_FORKPTY) || defined(HAVE_DEV_PTMX)
#ifdef HAVE_PTY_H
#include <pty.h>
#else
#ifdef HAVE_LIBUTIL_H
#include <libutil.h>
#endif /* HAVE_LIBUTIL_H */
#endif /* HAVE_PTY_H */
#ifdef HAVE_STROPTS_H
#include <stropts.h>
#endif
#endif /* defined(HAVE_OPENPTY) || defined(HAVE_FORKPTY) || defined(HAVE_DEV_PTMX */

#if defined(HAVE_OPENPTY) || defined(HAVE__GETPTY) || defined(HAVE_DEV_PTMX)
PyDoc_STRVAR(posix_openpty__doc__,
"openpty() -> (master_fd, slave_fd)\n\n\
Open a pseudo-terminal, returning open fd's for both master and slave end.\n");

static PyObject *
posix_openpty(PyObject *self, PyObject *noargs)
{
        int master_fd, slave_fd;
#ifndef HAVE_OPENPTY
        char * slave_name;
#endif
#if defined(HAVE_DEV_PTMX) && !defined(HAVE_OPENPTY) && !defined(HAVE__GETPTY)
        PyOS_sighandler_t sig_saved;
#ifdef sun
        extern char *ptsname(int fildes);
#endif
#endif

#ifdef HAVE_OPENPTY
        if (openpty(&master_fd, &slave_fd, NULL, NULL, NULL) != 0)
                return posix_error();
#elif defined(HAVE__GETPTY)
        slave_name = _getpty(&master_fd, O_RDWR, 0666, 0);
        if (slave_name == NULL)
                return posix_error();

        slave_fd = open(slave_name, O_RDWR);
        if (slave_fd < 0)
                return posix_error();
#else
        master_fd = open(DEV_PTY_FILE, O_RDWR | O_NOCTTY); /* open master */
        if (master_fd < 0)
                return posix_error();
        sig_saved = PyOS_setsig(SIGCHLD, SIG_DFL);
        /* change permission of slave */
        if (grantpt(master_fd) < 0) {
                PyOS_setsig(SIGCHLD, sig_saved);
                return posix_error();
        }
        /* unlock slave */
        if (unlockpt(master_fd) < 0) {
                PyOS_setsig(SIGCHLD, sig_saved);
                return posix_error();
        }
        PyOS_setsig(SIGCHLD, sig_saved);
        slave_name = ptsname(master_fd); /* get name of slave */
        if (slave_name == NULL)
                return posix_error();
        slave_fd = open(slave_name, O_RDWR | O_NOCTTY); /* open slave */
        if (slave_fd < 0)
                return posix_error();
#if !defined(__CYGWIN__) && !defined(HAVE_DEV_PTC)
        ioctl(slave_fd, I_PUSH, "ptem"); /* push ptem */
        ioctl(slave_fd, I_PUSH, "ldterm"); /* push ldterm */
#ifndef __hpux
        ioctl(slave_fd, I_PUSH, "ttcompat"); /* push ttcompat */
#endif /* __hpux */
#endif /* HAVE_CYGWIN */
#endif /* HAVE_OPENPTY */

        return Py_BuildValue("(ii)", master_fd, slave_fd);

}
#endif /* defined(HAVE_OPENPTY) || defined(HAVE__GETPTY) || defined(HAVE_DEV_PTMX) */

#ifdef HAVE_FORKPTY
PyDoc_STRVAR(posix_forkpty__doc__,
"forkpty() -> (pid, master_fd)\n\n\
Fork a new process with a new pseudo-terminal as controlling tty.\n\n\
Like fork(), return 0 as pid to child process, and PID of child to parent.\n\
To both, return fd of newly opened pseudo-terminal.\n");

static PyObject *
posix_forkpty(PyObject *self, PyObject *noargs)
{
        int master_fd = -1, pid;

        pid = forkpty(&master_fd, NULL, NULL, NULL);
        if (pid == -1)
                return posix_error();
        if (pid == 0)
                PyOS_AfterFork();
        return Py_BuildValue("(ii)", pid, master_fd);
}
#endif

#ifdef HAVE_GETEGID
PyDoc_STRVAR(posix_getegid__doc__,
"getegid() -> egid\n\n\
Return the current process's effective group id.");

static PyObject *
posix_getegid(PyObject *self, PyObject *noargs)
{
        return PyInt_FromLong((long)getegid());
}
#endif


#ifdef HAVE_GETEUID
PyDoc_STRVAR(posix_geteuid__doc__,
"geteuid() -> euid\n\n\
Return the current process's effective user id.");

static PyObject *
posix_geteuid(PyObject *self, PyObject *noargs)
{
        return PyInt_FromLong((long)geteuid());
}
#endif


#ifdef HAVE_GETGID
PyDoc_STRVAR(posix_getgid__doc__,
"getgid() -> gid\n\n\
Return the current process's group id.");

static PyObject *
posix_getgid(PyObject *self, PyObject *noargs)
{
        return PyInt_FromLong((long)getgid());
}
#endif


PyDoc_STRVAR(posix_getpid__doc__,
"getpid() -> pid\n\n\
Return the current process id");

static PyObject *
posix_getpid(PyObject *self, PyObject *noargs)
{
        return PyInt_FromLong((long)getpid());
}


#ifdef HAVE_GETGROUPS
PyDoc_STRVAR(posix_getgroups__doc__,
"getgroups() -> list of group IDs\n\n\
Return list of supplemental group IDs for the process.");

static PyObject *
posix_getgroups(PyObject *self, PyObject *noargs)
{
    PyObject *result = NULL;

#ifdef NGROUPS_MAX
#define MAX_GROUPS NGROUPS_MAX
#else
        /* defined to be 16 on Solaris7, so this should be a small number */
#define MAX_GROUPS 64
#endif
        gid_t grouplist[MAX_GROUPS];
        int n;

        n = getgroups(MAX_GROUPS, grouplist);
        if (n < 0)
            posix_error();
        else {
            result = PyList_New(n);
            if (result != NULL) {
                int i;
                for (i = 0; i < n; ++i) {
                    PyObject *o = PyInt_FromLong((long)grouplist[i]);
                    if (o == NULL) {
                        Py_DECREF(result);
                        result = NULL;
                        break;
                    }
                    PyList_SET_ITEM(result, i, o);
                }
            }
        }

    return result;
}
#endif

#ifdef HAVE_GETPGID
PyDoc_STRVAR(posix_getpgid__doc__,
"getpgid(pid) -> pgid\n\n\
Call the system call getpgid().");

static PyObject *
posix_getpgid(PyObject *self, PyObject *args)
{
        int pid, pgid;
        if (!PyArg_ParseTuple(args, "i:getpgid", &pid))
                return NULL;
        pgid = getpgid(pid);
        if (pgid < 0)
                return posix_error();
        return PyInt_FromLong((long)pgid);
}
#endif /* HAVE_GETPGID */


#ifdef HAVE_GETPGRP
PyDoc_STRVAR(posix_getpgrp__doc__,
"getpgrp() -> pgrp\n\n\
Return the current process group id.");

static PyObject *
posix_getpgrp(PyObject *self, PyObject *noargs)
{
#ifdef GETPGRP_HAVE_ARG
        return PyInt_FromLong((long)getpgrp(0));
#else /* GETPGRP_HAVE_ARG */
        return PyInt_FromLong((long)getpgrp());
#endif /* GETPGRP_HAVE_ARG */
}
#endif /* HAVE_GETPGRP */


#ifdef HAVE_SETPGRP
PyDoc_STRVAR(posix_setpgrp__doc__,
"setpgrp()\n\n\
Make this process a session leader.");

static PyObject *
posix_setpgrp(PyObject *self, PyObject *noargs)
{
#ifdef SETPGRP_HAVE_ARG
        if (setpgrp(0, 0) < 0)
#else /* SETPGRP_HAVE_ARG */
        if (setpgrp() < 0)
#endif /* SETPGRP_HAVE_ARG */
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}

#endif /* HAVE_SETPGRP */

#ifdef HAVE_GETPPID
PyDoc_STRVAR(posix_getppid__doc__,
"getppid() -> ppid\n\n\
Return the parent's process id.");

static PyObject *
posix_getppid(PyObject *self, PyObject *noargs)
{
        return PyInt_FromLong((long)getppid());
}
#endif


#ifdef HAVE_GETLOGIN
PyDoc_STRVAR(posix_getlogin__doc__,
"getlogin() -> string\n\n\
Return the actual login name.");

static PyObject *
posix_getlogin(PyObject *self, PyObject *noargs)
{
        PyObject *result = NULL;
        char *name;
        int old_errno = errno;

        errno = 0;
        name = getlogin();
        if (name == NULL) {
            if (errno)
                posix_error();
            else
                PyErr_SetString(PyExc_OSError,
                                "unable to determine login name");
        }
        else
            result = PyString_FromString(name);
        errno = old_errno;

    return result;
}
#endif

#ifdef HAVE_GETUID
PyDoc_STRVAR(posix_getuid__doc__,
"getuid() -> uid\n\n\
Return the current process's user id.");

static PyObject *
posix_getuid(PyObject *self, PyObject *noargs)
{
        return PyInt_FromLong((long)getuid());
}
#endif


#ifdef HAVE_KILL
PyDoc_STRVAR(posix_kill__doc__,
"kill(pid, sig)\n\n\
Kill a process with a signal.");

static PyObject *
posix_kill(PyObject *self, PyObject *args)
{
        int pid, sig;
        if (!PyArg_ParseTuple(args, "ii:kill", &pid, &sig))
                return NULL;
#if defined(PYOS_OS2) && !defined(PYCC_GCC)
    if (sig == XCPT_SIGNAL_INTR || sig == XCPT_SIGNAL_BREAK) {
        APIRET rc;
        if ((rc = DosSendSignalException(pid, sig)) != NO_ERROR)
            return os2_error(rc);

    } else if (sig == XCPT_SIGNAL_KILLPROC) {
        APIRET rc;
        if ((rc = DosKillProcess(DKP_PROCESS, pid)) != NO_ERROR)
            return os2_error(rc);

    } else
        return NULL; /* Unrecognized Signal Requested */
#else
        if (kill(pid, sig) == -1)
                return posix_error();
#endif
        Py_INCREF(Py_None);
        return Py_None;
}
#endif

#ifdef HAVE_KILLPG
PyDoc_STRVAR(posix_killpg__doc__,
"killpg(pgid, sig)\n\n\
Kill a process group with a signal.");

static PyObject *
posix_killpg(PyObject *self, PyObject *args)
{
        int pgid, sig;
        if (!PyArg_ParseTuple(args, "ii:killpg", &pgid, &sig))
                return NULL;
        if (killpg(pgid, sig) == -1)
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}
#endif

#ifdef HAVE_PLOCK

#ifdef HAVE_SYS_LOCK_H
#include <sys/lock.h>
#endif

PyDoc_STRVAR(posix_plock__doc__,
"plock(op)\n\n\
Lock program segments into memory.");

static PyObject *
posix_plock(PyObject *self, PyObject *args)
{
        int op;
        if (!PyArg_ParseTuple(args, "i:plock", &op))
                return NULL;
        if (plock(op) == -1)
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}
#endif


#ifdef HAVE_POPEN
PyDoc_STRVAR(posix_popen__doc__,
"popen(command [, mode='r' [, bufsize]]) -> pipe\n\n\
Open a pipe to/from a command returning a file object.");

#if defined(PYOS_OS2)
#if defined(PYCC_VACPP)
static int
async_system(const char *command)
{
        char errormsg[256], args[1024];
        RESULTCODES rcodes;
        APIRET rc;

        char *shell = getenv("COMSPEC");
        if (!shell)
                shell = "cmd";

        /* avoid overflowing the argument buffer */
        if (strlen(shell) + 3 + strlen(command) >= 1024)
                return ERROR_NOT_ENOUGH_MEMORY

        args[0] = '\0';
        strcat(args, shell);
        strcat(args, "/c ");
        strcat(args, command);

        /* execute asynchronously, inheriting the environment */
        rc = DosExecPgm(errormsg,
                        sizeof(errormsg),
                        EXEC_ASYNC,
                        args,
                        NULL,
                        &rcodes,
                        shell);
        return rc;
}

static FILE *
popen(const char *command, const char *mode, int pipesize, int *err)
{
        int oldfd, tgtfd;
        HFILE pipeh[2];
        APIRET rc;

        /* mode determines which of stdin or stdout is reconnected to
         * the pipe to the child
         */
        if (strchr(mode, 'r') != NULL) {
                tgt_fd = 1;     /* stdout */
        } else if (strchr(mode, 'w')) {
                tgt_fd = 0;     /* stdin */
        } else {
                *err = ERROR_INVALID_ACCESS;
                return NULL;
        }

        /* setup the pipe */
        if ((rc = DosCreatePipe(&pipeh[0], &pipeh[1], pipesize)) != NO_ERROR) {
                *err = rc;
                return NULL;
        }

        /* prevent other threads accessing stdio */
        DosEnterCritSec();

        /* reconnect stdio and execute child */
        oldfd = dup(tgtfd);
        close(tgtfd);
        if (dup2(pipeh[tgtfd], tgtfd) == 0) {
                DosClose(pipeh[tgtfd]);
                rc = async_system(command);
        }

        /* restore stdio */
        dup2(oldfd, tgtfd);
        close(oldfd);

        /* allow other threads access to stdio */
        DosExitCritSec();

        /* if execution of child was successful return file stream */
        if (rc == NO_ERROR)
                return fdopen(pipeh[1 - tgtfd], mode);
        else {
                DosClose(pipeh[1 - tgtfd]);
                *err = rc;
                return NULL;
        }
}

static PyObject *
posix_popen(PyObject *self, PyObject *args)
{
        char *name;
        char *mode = "r";
        int   err, bufsize = -1;
        FILE *fp;
        PyObject *f;
        if (!PyArg_ParseTuple(args, "s|si:popen", &name, &mode, &bufsize))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        fp = popen(name, mode, (bufsize > 0) ? bufsize : 4096, &err);
        Py_END_ALLOW_THREADS
        if (fp == NULL)
                return os2_error(err);

        f = PyFile_FromFile(fp, name, mode, fclose);
        if (f != NULL)
                PyFile_SetBufSize(f, bufsize);
        return f;
}

#elif defined(PYCC_GCC)

/* standard posix version of popen() support */
static PyObject *
posix_popen(PyObject *self, PyObject *args)
{
        char *name;
        char *mode = "r";
        int bufsize = -1;
        FILE *fp;
        PyObject *f;
        if (!PyArg_ParseTuple(args, "s|si:popen", &name, &mode, &bufsize))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        fp = popen(name, mode);
        Py_END_ALLOW_THREADS
        if (fp == NULL)
                return posix_error();
        f = PyFile_FromFile(fp, name, mode, pclose);
        if (f != NULL)
                PyFile_SetBufSize(f, bufsize);
        return f;
}

/* fork() under OS/2 has lots'o'warts
 * EMX supports pipe() and spawn*() so we can synthesize popen[234]()
 * most of this code is a ripoff of the win32 code, but using the
 * capabilities of EMX's C library routines
 */

/* These tell _PyPopen() whether to return 1, 2, or 3 file objects. */
#define POPEN_1 1
#define POPEN_2 2
#define POPEN_3 3
#define POPEN_4 4

static PyObject *_PyPopen(char *, int, int, int);
static int _PyPclose(FILE *file);

/*
 * Internal dictionary mapping popen* file pointers to process handles,
 * for use when retrieving the process exit code.  See _PyPclose() below
 * for more information on this dictionary's use.
 */
static PyObject *_PyPopenProcs = NULL;

/* os2emx version of popen2()
 *
 * The result of this function is a pipe (file) connected to the
 * process's stdin, and a pipe connected to the process's stdout.
 */

static PyObject *
os2emx_popen2(PyObject *self, PyObject  *args)
{
        PyObject *f;
        int tm=0;

        char *cmdstring;
        char *mode = "t";
        int bufsize = -1;
        if (!PyArg_ParseTuple(args, "s|si:popen2", &cmdstring, &mode, &bufsize))
                return NULL;

        if (*mode == 't')
                tm = O_TEXT;
        else if (*mode != 'b') {
                PyErr_SetString(PyExc_ValueError, "mode must be 't' or 'b'");
                return NULL;
        } else
                tm = O_BINARY;

        f = _PyPopen(cmdstring, tm, POPEN_2, bufsize);

        return f;
}

/*
 * Variation on os2emx.popen2
 *
 * The result of this function is 3 pipes - the process's stdin,
 * stdout and stderr
 */

static PyObject *
os2emx_popen3(PyObject *self, PyObject *args)
{
        PyObject *f;
        int tm = 0;

        char *cmdstring;
        char *mode = "t";
        int bufsize = -1;
        if (!PyArg_ParseTuple(args, "s|si:popen3", &cmdstring, &mode, &bufsize))
                return NULL;

        if (*mode == 't')
                tm = O_TEXT;
        else if (*mode != 'b') {
                PyErr_SetString(PyExc_ValueError, "mode must be 't' or 'b'");
                return NULL;
        } else
                tm = O_BINARY;

        f = _PyPopen(cmdstring, tm, POPEN_3, bufsize);

        return f;
}

/*
 * Variation on os2emx.popen2
 *
 * The result of this function is 2 pipes - the processes stdin,
 * and stdout+stderr combined as a single pipe.
 */

static PyObject *
os2emx_popen4(PyObject *self, PyObject  *args)
{
        PyObject *f;
        int tm = 0;

        char *cmdstring;
        char *mode = "t";
        int bufsize = -1;
        if (!PyArg_ParseTuple(args, "s|si:popen4", &cmdstring, &mode, &bufsize))
                return NULL;

        if (*mode == 't')
                tm = O_TEXT;
        else if (*mode != 'b') {
                PyErr_SetString(PyExc_ValueError, "mode must be 't' or 'b'");
                return NULL;
        } else
                tm = O_BINARY;

        f = _PyPopen(cmdstring, tm, POPEN_4, bufsize);

        return f;
}

/* a couple of structures for convenient handling of multiple
 * file handles and pipes
 */
struct file_ref
{
        int handle;
        int flags;
};

struct pipe_ref
{
        int rd;
        int wr;
};

/* The following code is derived from the win32 code */

static PyObject *
_PyPopen(char *cmdstring, int mode, int n, int bufsize)
{
        struct file_ref stdio[3];
        struct pipe_ref p_fd[3];
        FILE *p_s[3];
        int file_count, i, pipe_err, pipe_pid;
        char *shell, *sh_name, *opt, *rd_mode, *wr_mode;
        PyObject *f, *p_f[3];

        /* file modes for subsequent fdopen's on pipe handles */
        if (mode == O_TEXT)
        {
                rd_mode = "rt";
                wr_mode = "wt";
        }
        else
        {
                rd_mode = "rb";
                wr_mode = "wb";
        }

        /* prepare shell references */
        if ((shell = getenv("EMXSHELL")) == NULL)
                if ((shell = getenv("COMSPEC")) == NULL)
                {
                        errno = ENOENT;
                        return posix_error();
                }

        sh_name = _getname(shell);
        if (stricmp(sh_name, "cmd.exe") == 0 || stricmp(sh_name, "4os2.exe") == 0)
                opt = "/c";
        else
                opt = "-c";

        /* save current stdio fds + their flags, and set not inheritable */
        i = pipe_err = 0;
        while (pipe_err >= 0 && i < 3)
        {
                pipe_err = stdio[i].handle = dup(i);
                stdio[i].flags = fcntl(i, F_GETFD, 0);
                fcntl(stdio[i].handle, F_SETFD, stdio[i].flags | FD_CLOEXEC);
                i++;
        }
        if (pipe_err < 0)
        {
                /* didn't get them all saved - clean up and bail out */
                int saved_err = errno;
                while (i-- > 0)
                {
                        close(stdio[i].handle);
                }
                errno = saved_err;
                return posix_error();
        }

        /* create pipe ends */
        file_count = 2;
        if (n == POPEN_3)
                file_count = 3;
        i = pipe_err = 0;
        while ((pipe_err == 0) && (i < file_count))
                pipe_err = pipe((int *)&p_fd[i++]);
        if (pipe_err < 0)
        {
                /* didn't get them all made - clean up and bail out */
                while (i-- > 0)
                {
                        close(p_fd[i].wr);
                        close(p_fd[i].rd);
                }
                errno = EPIPE;
                return posix_error();
        }

        /* change the actual standard IO streams over temporarily,
         * making the retained pipe ends non-inheritable
         */
        pipe_err = 0;

        /* - stdin */
        if (dup2(p_fd[0].rd, 0) == 0)
        {
                close(p_fd[0].rd);
                i = fcntl(p_fd[0].wr, F_GETFD, 0);
                fcntl(p_fd[0].wr, F_SETFD, i | FD_CLOEXEC);
                if ((p_s[0] = fdopen(p_fd[0].wr, wr_mode)) == NULL)
                {
                        close(p_fd[0].wr);
                        pipe_err = -1;
                }
        }
        else
        {
                pipe_err = -1;
        }

        /* - stdout */
        if (pipe_err == 0)
        {
                if (dup2(p_fd[1].wr, 1) == 1)
                {
                        close(p_fd[1].wr);
                        i = fcntl(p_fd[1].rd, F_GETFD, 0);
                        fcntl(p_fd[1].rd, F_SETFD, i | FD_CLOEXEC);
                        if ((p_s[1] = fdopen(p_fd[1].rd, rd_mode)) == NULL)
                        {
                                close(p_fd[1].rd);
                                pipe_err = -1;
                        }
                }
                else
                {
                        pipe_err = -1;
                }
        }

        /* - stderr, as required */
        if (pipe_err == 0)
                switch (n)
                {
                        case POPEN_3:
                        {
                                if (dup2(p_fd[2].wr, 2) == 2)
                                {
                                        close(p_fd[2].wr);
                                        i = fcntl(p_fd[2].rd, F_GETFD, 0);
                                        fcntl(p_fd[2].rd, F_SETFD, i | FD_CLOEXEC);
                                        if ((p_s[2] = fdopen(p_fd[2].rd, rd_mode)) == NULL)
                                        {
                                                close(p_fd[2].rd);
                                                pipe_err = -1;
                                        }
                                }
                                else
                                {
                                        pipe_err = -1;
                                }
                                break;
                        }

                        case POPEN_4:
                        {
                                if (dup2(1, 2) != 2)
                                {
                                        pipe_err = -1;
                                }
                                break;
                        }
                }

        /* spawn the child process */
        if (pipe_err == 0)
        {
                pipe_pid = spawnlp(P_NOWAIT, shell, shell, opt, cmdstring, (char *)0);
                if (pipe_pid == -1)
                {
                        pipe_err = -1;
                }
                else
                {
                        /* save the PID into the FILE structure
                         * NOTE: this implementation doesn't actually
                         * take advantage of this, but do it for
                         * completeness - AIM Apr01
                         */
                        for (i = 0; i < file_count; i++)
                                p_s[i]->_pid = pipe_pid;
                }
        }

        /* reset standard IO to normal */
        for (i = 0; i < 3; i++)
        {
                dup2(stdio[i].handle, i);
                fcntl(i, F_SETFD, stdio[i].flags);
                close(stdio[i].handle);
        }

        /* if any remnant problems, clean up and bail out */
        if (pipe_err < 0)
        {
                for (i = 0; i < 3; i++)
                {
                        close(p_fd[i].rd);
                        close(p_fd[i].wr);
                }
                errno = EPIPE;
                return posix_error_with_filename(cmdstring);
        }

        /* build tuple of file objects to return */
        if ((p_f[0] = PyFile_FromFile(p_s[0], cmdstring, wr_mode, _PyPclose)) != NULL)
                PyFile_SetBufSize(p_f[0], bufsize);
        if ((p_f[1] = PyFile_FromFile(p_s[1], cmdstring, rd_mode, _PyPclose)) != NULL)
                PyFile_SetBufSize(p_f[1], bufsize);
        if (n == POPEN_3)
        {
                if ((p_f[2] = PyFile_FromFile(p_s[2], cmdstring, rd_mode, _PyPclose)) != NULL)
                        PyFile_SetBufSize(p_f[0], bufsize);
                f = PyTuple_Pack(3, p_f[0], p_f[1], p_f[2]);
        }
        else
                f = PyTuple_Pack(2, p_f[0], p_f[1]);

        /*
         * Insert the files we've created into the process dictionary
         * all referencing the list with the process handle and the
         * initial number of files (see description below in _PyPclose).
         * Since if _PyPclose later tried to wait on a process when all
         * handles weren't closed, it could create a deadlock with the
         * child, we spend some energy here to try to ensure that we
         * either insert all file handles into the dictionary or none
         * at all.  It's a little clumsy with the various popen modes
         * and variable number of files involved.
         */
        if (!_PyPopenProcs)
        {
                _PyPopenProcs = PyDict_New();
        }

        if (_PyPopenProcs)
        {
                PyObject *procObj, *pidObj, *intObj, *fileObj[3];
                int ins_rc[3];

                fileObj[0] = fileObj[1] = fileObj[2] = NULL;
                ins_rc[0]  = ins_rc[1]  = ins_rc[2]  = 0;

                procObj = PyList_New(2);
                pidObj = PyInt_FromLong((long) pipe_pid);
                intObj = PyInt_FromLong((long) file_count);

                if (procObj && pidObj && intObj)
                {
                        PyList_SetItem(procObj, 0, pidObj);
                        PyList_SetItem(procObj, 1, intObj);

                        fileObj[0] = PyLong_FromVoidPtr(p_s[0]);
                        if (fileObj[0])
                        {
                            ins_rc[0] = PyDict_SetItem(_PyPopenProcs,
                                                       fileObj[0],
                                                       procObj);
                        }
                        fileObj[1] = PyLong_FromVoidPtr(p_s[1]);
                        if (fileObj[1])
                        {
                            ins_rc[1] = PyDict_SetItem(_PyPopenProcs,
                                                       fileObj[1],
                                                       procObj);
                        }
                        if (file_count >= 3)
                        {
                                fileObj[2] = PyLong_FromVoidPtr(p_s[2]);
                                if (fileObj[2])
                                {
                                    ins_rc[2] = PyDict_SetItem(_PyPopenProcs,
                                                               fileObj[2],
                                                               procObj);
                                }
                        }

                        if (ins_rc[0] < 0 || !fileObj[0] ||
                            ins_rc[1] < 0 || (file_count > 1 && !fileObj[1]) ||
                            ins_rc[2] < 0 || (file_count > 2 && !fileObj[2]))
                        {
                                /* Something failed - remove any dictionary
                                 * entries that did make it.
                                 */
                                if (!ins_rc[0] && fileObj[0])
                                {
                                        PyDict_DelItem(_PyPopenProcs,
                                                        fileObj[0]);
                                }
                                if (!ins_rc[1] && fileObj[1])
                                {
                                        PyDict_DelItem(_PyPopenProcs,
                                                        fileObj[1]);
                                }
                                if (!ins_rc[2] && fileObj[2])
                                {
                                        PyDict_DelItem(_PyPopenProcs,
                                                        fileObj[2]);
                                }
                        }
                }

                /*
                 * Clean up our localized references for the dictionary keys
                 * and value since PyDict_SetItem will Py_INCREF any copies
                 * that got placed in the dictionary.
                 */
                Py_XDECREF(procObj);
                Py_XDECREF(fileObj[0]);
                Py_XDECREF(fileObj[1]);
                Py_XDECREF(fileObj[2]);
        }

        /* Child is launched. */
        return f;
}

/*
 * Wrapper for fclose() to use for popen* files, so we can retrieve the
 * exit code for the child process and return as a result of the close.
 *
 * This function uses the _PyPopenProcs dictionary in order to map the
 * input file pointer to information about the process that was
 * originally created by the popen* call that created the file pointer.
 * The dictionary uses the file pointer as a key (with one entry
 * inserted for each file returned by the original popen* call) and a
 * single list object as the value for all files from a single call.
 * The list object contains the Win32 process handle at [0], and a file
 * count at [1], which is initialized to the total number of file
 * handles using that list.
 *
 * This function closes whichever handle it is passed, and decrements
 * the file count in the dictionary for the process handle pointed to
 * by this file.  On the last close (when the file count reaches zero),
 * this function will wait for the child process and then return its
 * exit code as the result of the close() operation.  This permits the
 * files to be closed in any order - it is always the close() of the
 * final handle that will return the exit code.
 *
 * NOTE: This function is currently called with the GIL released.
 * hence we use the GILState API to manage our state.
 */

static int _PyPclose(FILE *file)
{
        int result;
        int exit_code;
        int pipe_pid;
        PyObject *procObj, *pidObj, *intObj, *fileObj;
        int file_count;
#ifdef WITH_THREAD
        PyGILState_STATE state;
#endif

        /* Close the file handle first, to ensure it can't block the
         * child from exiting if it's the last handle.
         */
        result = fclose(file);

#ifdef WITH_THREAD
        state = PyGILState_Ensure();
#endif
        if (_PyPopenProcs)
        {
                if ((fileObj = PyLong_FromVoidPtr(file)) != NULL &&
                    (procObj = PyDict_GetItem(_PyPopenProcs,
                                              fileObj)) != NULL &&
                    (pidObj = PyList_GetItem(procObj,0)) != NULL &&
                    (intObj = PyList_GetItem(procObj,1)) != NULL)
                {
                        pipe_pid = (int) PyInt_AsLong(pidObj);
                        file_count = (int) PyInt_AsLong(intObj);

                        if (file_count > 1)
                        {
                                /* Still other files referencing process */
                                file_count--;
                                PyList_SetItem(procObj,1,
                                               PyInt_FromLong((long) file_count));
                        }
                        else
                        {
                                /* Last file for this process */
                                if (result != EOF &&
                                    waitpid(pipe_pid, &exit_code, 0) == pipe_pid)
                                {
                                        /* extract exit status */
                                        if (WIFEXITED(exit_code))
                                        {
                                                result = WEXITSTATUS(exit_code);
                                        }
                                        else
                                        {
                                                errno = EPIPE;
                                                result = -1;
                                        }
                                }
                                else
                                {
                                        /* Indicate failure - this will cause the file object
                                         * to raise an I/O error and translate the last
                                         * error code from errno.  We do have a problem with
                                         * last errors that overlap the normal errno table,
                                         * but that's a consistent problem with the file object.
                                         */
                                        result = -1;
                                }
                        }

                        /* Remove this file pointer from dictionary */
                        PyDict_DelItem(_PyPopenProcs, fileObj);

                        if (PyDict_Size(_PyPopenProcs) == 0)
                        {
                                Py_DECREF(_PyPopenProcs);
                                _PyPopenProcs = NULL;
                        }

                } /* if object retrieval ok */

                Py_XDECREF(fileObj);
        } /* if _PyPopenProcs */

#ifdef WITH_THREAD
        PyGILState_Release(state);
#endif
        return result;
}

#endif /* PYCC_??? */

#elif defined(MS_WINDOWS)

/*
 * Portable 'popen' replacement for Win32.
 *
 * Written by Bill Tutt <[email protected]>.  Minor tweaks
 * and 2.0 integration by Fredrik Lundh <[email protected]>
 * Return code handling by David Bolen <[email protected]>.
 */

#include <malloc.h>
#include <io.h>
#include <fcntl.h>

/* These tell _PyPopen() wether to return 1, 2, or 3 file objects. */
#define POPEN_1 1
#define POPEN_2 2
#define POPEN_3 3
#define POPEN_4 4

static PyObject *_PyPopen(char *, int, int);
static int _PyPclose(FILE *file);

/*
 * Internal dictionary mapping popen* file pointers to process handles,
 * for use when retrieving the process exit code.  See _PyPclose() below
 * for more information on this dictionary's use.
 */
static PyObject *_PyPopenProcs = NULL;


/* popen that works from a GUI.
 *
 * The result of this function is a pipe (file) connected to the
 * processes stdin or stdout, depending on the requested mode.
 */

static PyObject *
posix_popen(PyObject *self, PyObject *args)
{
        PyObject *f;
        int tm = 0;

        char *cmdstring;
        char *mode = "r";
        int bufsize = -1;
        if (!PyArg_ParseTuple(args, "s|si:popen", &cmdstring, &mode, &bufsize))
                return NULL;

        if (*mode == 'r')
                tm = _O_RDONLY;
        else if (*mode != 'w') {
                PyErr_SetString(PyExc_ValueError, "popen() arg 2 must be 'r' or 'w'");
                return NULL;
        } else
                tm = _O_WRONLY;

        if (bufsize != -1) {
                PyErr_SetString(PyExc_ValueError, "popen() arg 3 must be -1");
                return NULL;
        }

        if (*(mode+1) == 't')
                f = _PyPopen(cmdstring, tm | _O_TEXT, POPEN_1);
        else if (*(mode+1) == 'b')
                f = _PyPopen(cmdstring, tm | _O_BINARY, POPEN_1);
        else
                f = _PyPopen(cmdstring, tm | _O_TEXT, POPEN_1);

        return f;
}

/* Variation on win32pipe.popen
 *
 * The result of this function is a pipe (file) connected to the
 * process's stdin, and a pipe connected to the process's stdout.
 */

static PyObject *
win32_popen2(PyObject *self, PyObject  *args)
{
        PyObject *f;
        int tm=0;

        char *cmdstring;
        char *mode = "t";
        int bufsize = -1;
        if (!PyArg_ParseTuple(args, "s|si:popen2", &cmdstring, &mode, &bufsize))
                return NULL;

        if (*mode == 't')
                tm = _O_TEXT;
        else if (*mode != 'b') {
                PyErr_SetString(PyExc_ValueError, "popen2() arg 2 must be 't' or 'b'");
                return NULL;
        } else
                tm = _O_BINARY;

        if (bufsize != -1) {
                PyErr_SetString(PyExc_ValueError, "popen2() arg 3 must be -1");
                return NULL;
        }

        f = _PyPopen(cmdstring, tm, POPEN_2);

        return f;
}

/*
 * Variation on <om win32pipe.popen>
 *
 * The result of this function is 3 pipes - the process's stdin,
 * stdout and stderr
 */

static PyObject *
win32_popen3(PyObject *self, PyObject *args)
{
        PyObject *f;
        int tm = 0;

        char *cmdstring;
        char *mode = "t";
        int bufsize = -1;
        if (!PyArg_ParseTuple(args, "s|si:popen3", &cmdstring, &mode, &bufsize))
                return NULL;

        if (*mode == 't')
                tm = _O_TEXT;
        else if (*mode != 'b') {
                PyErr_SetString(PyExc_ValueError, "popen3() arg 2 must be 't' or 'b'");
                return NULL;
        } else
                tm = _O_BINARY;

        if (bufsize != -1) {
                PyErr_SetString(PyExc_ValueError, "popen3() arg 3 must be -1");
                return NULL;
        }

        f = _PyPopen(cmdstring, tm, POPEN_3);

        return f;
}

/*
 * Variation on win32pipe.popen
 *
 * The result of this function is 2 pipes - the processes stdin,
 * and stdout+stderr combined as a single pipe.
 */

static PyObject *
win32_popen4(PyObject *self, PyObject  *args)
{
        PyObject *f;
        int tm = 0;

        char *cmdstring;
        char *mode = "t";
        int bufsize = -1;
        if (!PyArg_ParseTuple(args, "s|si:popen4", &cmdstring, &mode, &bufsize))
                return NULL;

        if (*mode == 't')
                tm = _O_TEXT;
        else if (*mode != 'b') {
                PyErr_SetString(PyExc_ValueError, "popen4() arg 2 must be 't' or 'b'");
                return NULL;
        } else
                tm = _O_BINARY;

        if (bufsize != -1) {
                PyErr_SetString(PyExc_ValueError, "popen4() arg 3 must be -1");
                return NULL;
        }

        f = _PyPopen(cmdstring, tm, POPEN_4);

        return f;
}

static BOOL
_PyPopenCreateProcess(char *cmdstring,
                      HANDLE hStdin,
                      HANDLE hStdout,
                      HANDLE hStderr,
                      HANDLE *hProcess)
{
        PROCESS_INFORMATION piProcInfo;
        STARTUPINFO siStartInfo;
        DWORD dwProcessFlags = 0;  /* no NEW_CONSOLE by default for Ctrl+C handling */
        char *s1,*s2, *s3 = " /c ";
        const char *szConsoleSpawn = "w9xpopen.exe";
        int i;
        Py_ssize_t x;

        if (i = GetEnvironmentVariable("COMSPEC",NULL,0)) {
                char *comshell;

                s1 = (char *)alloca(i);
                if (!(x = GetEnvironmentVariable("COMSPEC", s1, i)))
                        /* x < i, so x fits into an integer */
                        return (int)x;

                /* Explicitly check if we are using COMMAND.COM.  If we are
                 * then use the w9xpopen hack.
                 */
                comshell = s1 + x;
                while (comshell >= s1 && *comshell != '\\')
                        --comshell;
                ++comshell;

                if (GetVersion() < 0x80000000 &&
                    _stricmp(comshell, "command.com") != 0) {
                        /* NT/2000 and not using command.com. */
                        x = i + strlen(s3) + strlen(cmdstring) + 1;
                        s2 = (char *)alloca(x);
                        ZeroMemory(s2, x);
                        PyOS_snprintf(s2, x, "%s%s%s", s1, s3, cmdstring);
                }
                else {
                        /*
                         * Oh gag, we're on Win9x or using COMMAND.COM. Use
                         * the workaround listed in KB: Q150956
                         */
                        char modulepath[_MAX_PATH];
                        struct stat statinfo;
                        GetModuleFileName(NULL, modulepath, sizeof(modulepath));
                        for (x = i = 0; modulepath[i]; i++)
                                if (modulepath[i] == SEP)
                                        x = i+1;
                        modulepath[x] = '\0';
                        /* Create the full-name to w9xpopen, so we can test it exists */
                        strncat(modulepath,
                                szConsoleSpawn,
                                (sizeof(modulepath)/sizeof(modulepath[0]))
                                       -strlen(modulepath));
                        if (stat(modulepath, &statinfo) != 0) {
                                /* Eeek - file-not-found - possibly an embedding
                                   situation - see if we can locate it in sys.prefix
                                */
                                strncpy(modulepath,
                                        Py_GetExecPrefix(),
                                        sizeof(modulepath)/sizeof(modulepath[0]));
                                if (modulepath[strlen(modulepath)-1] != '\\')
                                        strcat(modulepath, "\\");
                                strncat(modulepath,
                                        szConsoleSpawn,
                                        (sizeof(modulepath)/sizeof(modulepath[0]))
                                               -strlen(modulepath));
                                /* No where else to look - raise an easily identifiable
                                   error, rather than leaving Windows to report
                                   "file not found" - as the user is probably blissfully
                                   unaware this shim EXE is used, and it will confuse them.
                                   (well, it confused me for a while ;-)
                                */
                                if (stat(modulepath, &statinfo) != 0) {
                                        PyErr_Format(PyExc_RuntimeError,
                                            "Can not locate '%s' which is needed "
                                            "for popen to work with your shell "
                                            "or platform.",
                                            szConsoleSpawn);
                                        return FALSE;
                                }
                        }
                        x = i + strlen(s3) + strlen(cmdstring) + 1 +
                                strlen(modulepath) +
                                strlen(szConsoleSpawn) + 1;

                        s2 = (char *)alloca(x);
                        ZeroMemory(s2, x);
                        /* To maintain correct argument passing semantics,
                           we pass the command-line as it stands, and allow
                           quoting to be applied.  w9xpopen.exe will then
                           use its argv vector, and re-quote the necessary
                           args for the ultimate child process.
                        */
                        PyOS_snprintf(
                                s2, x,
                                "\"%s\" %s%s%s",
                                modulepath,
                                s1,
                                s3,
                                cmdstring);
                        /* Not passing CREATE_NEW_CONSOLE has been known to
                           cause random failures on win9x.  Specifically a
                           dialog:
                           "Your program accessed mem currently in use at xxx"
                           and a hopeful warning about the stability of your
                           system.
                           Cost is Ctrl+C wont kill children, but anyone
                           who cares can have a go!
                        */
                        dwProcessFlags |= CREATE_NEW_CONSOLE;
                }
        }

        /* Could be an else here to try cmd.exe / command.com in the path
           Now we'll just error out.. */
        else {
                PyErr_SetString(PyExc_RuntimeError,
                        "Cannot locate a COMSPEC environment variable to "
                        "use as the shell");
                return FALSE;
        }

        ZeroMemory(&siStartInfo, sizeof(STARTUPINFO));
        siStartInfo.cb = sizeof(STARTUPINFO);
        siStartInfo.dwFlags = STARTF_USESTDHANDLES | STARTF_USESHOWWINDOW;
        siStartInfo.hStdInput = hStdin;
        siStartInfo.hStdOutput = hStdout;
        siStartInfo.hStdError = hStderr;
        siStartInfo.wShowWindow = SW_HIDE;

        if (CreateProcess(NULL,
                          s2,
                          NULL,
                          NULL,
                          TRUE,
                          dwProcessFlags,
                          NULL,
                          NULL,
                          &siStartInfo,
                          &piProcInfo) ) {
                /* Close the handles now so anyone waiting is woken. */
                CloseHandle(piProcInfo.hThread);

                /* Return process handle */
                *hProcess = piProcInfo.hProcess;
                return TRUE;
        }
        win32_error("CreateProcess", s2);
        return FALSE;
}

/* The following code is based off of KB: Q190351 */

static PyObject *
_PyPopen(char *cmdstring, int mode, int n)
{
        HANDLE hChildStdinRd, hChildStdinWr, hChildStdoutRd, hChildStdoutWr,
                hChildStderrRd, hChildStderrWr, hChildStdinWrDup, hChildStdoutRdDup,
                hChildStderrRdDup, hProcess; /* hChildStdoutWrDup; */

        SECURITY_ATTRIBUTES saAttr;
        BOOL fSuccess;
        int fd1, fd2, fd3;
        FILE *f1, *f2, *f3;
        long file_count;
        PyObject *f;

        saAttr.nLength = sizeof(SECURITY_ATTRIBUTES);
        saAttr.bInheritHandle = TRUE;
        saAttr.lpSecurityDescriptor = NULL;

        if (!CreatePipe(&hChildStdinRd, &hChildStdinWr, &saAttr, 0))
                return win32_error("CreatePipe", NULL);

        /* Create new output read handle and the input write handle. Set
         * the inheritance properties to FALSE. Otherwise, the child inherits
         * these handles; resulting in non-closeable handles to the pipes
         * being created. */
         fSuccess = DuplicateHandle(GetCurrentProcess(), hChildStdinWr,
                                    GetCurrentProcess(), &hChildStdinWrDup, 0,
                                    FALSE,
                                    DUPLICATE_SAME_ACCESS);
         if (!fSuccess)
                 return win32_error("DuplicateHandle", NULL);

         /* Close the inheritable version of ChildStdin
        that we're using. */
         CloseHandle(hChildStdinWr);

         if (!CreatePipe(&hChildStdoutRd, &hChildStdoutWr, &saAttr, 0))
                 return win32_error("CreatePipe", NULL);

         fSuccess = DuplicateHandle(GetCurrentProcess(), hChildStdoutRd,
                                    GetCurrentProcess(), &hChildStdoutRdDup, 0,
                                    FALSE, DUPLICATE_SAME_ACCESS);
         if (!fSuccess)
                 return win32_error("DuplicateHandle", NULL);

         /* Close the inheritable version of ChildStdout
                that we're using. */
         CloseHandle(hChildStdoutRd);

         if (n != POPEN_4) {
                 if (!CreatePipe(&hChildStderrRd, &hChildStderrWr, &saAttr, 0))
                         return win32_error("CreatePipe", NULL);
                 fSuccess = DuplicateHandle(GetCurrentProcess(),
                                            hChildStderrRd,
                                            GetCurrentProcess(),
                                            &hChildStderrRdDup, 0,
                                            FALSE, DUPLICATE_SAME_ACCESS);
                 if (!fSuccess)
                         return win32_error("DuplicateHandle", NULL);
                 /* Close the inheritable version of ChildStdErr that we're using. */
                 CloseHandle(hChildStderrRd);
         }

         switch (n) {
         case POPEN_1:
                 switch (mode & (_O_RDONLY | _O_TEXT | _O_BINARY | _O_WRONLY)) {
                 case _O_WRONLY | _O_TEXT:
                         /* Case for writing to child Stdin in text mode. */
                         fd1 = _open_osfhandle((Py_intptr_t)hChildStdinWrDup, mode);
                         f1 = _fdopen(fd1, "w");
                         f = PyFile_FromFile(f1, cmdstring, "w", _PyPclose);
                         PyFile_SetBufSize(f, 0);
                         /* We don't care about these pipes anymore, so close them. */
                         CloseHandle(hChildStdoutRdDup);
                         CloseHandle(hChildStderrRdDup);
                         break;

                 case _O_RDONLY | _O_TEXT:
                         /* Case for reading from child Stdout in text mode. */
                         fd1 = _open_osfhandle((Py_intptr_t)hChildStdoutRdDup, mode);
                         f1 = _fdopen(fd1, "r");
                         f = PyFile_FromFile(f1, cmdstring, "r", _PyPclose);
                         PyFile_SetBufSize(f, 0);
                         /* We don't care about these pipes anymore, so close them. */
                         CloseHandle(hChildStdinWrDup);
                         CloseHandle(hChildStderrRdDup);
                         break;

                 case _O_RDONLY | _O_BINARY:
                         /* Case for readinig from child Stdout in binary mode. */
                         fd1 = _open_osfhandle((Py_intptr_t)hChildStdoutRdDup, mode);
                         f1 = _fdopen(fd1, "rb");
                         f = PyFile_FromFile(f1, cmdstring, "rb", _PyPclose);
                         PyFile_SetBufSize(f, 0);
                         /* We don't care about these pipes anymore, so close them. */
                         CloseHandle(hChildStdinWrDup);
                         CloseHandle(hChildStderrRdDup);
                         break;

                 case _O_WRONLY | _O_BINARY:
                         /* Case for writing to child Stdin in binary mode. */
                         fd1 = _open_osfhandle((Py_intptr_t)hChildStdinWrDup, mode);
                         f1 = _fdopen(fd1, "wb");
                         f = PyFile_FromFile(f1, cmdstring, "wb", _PyPclose);
                         PyFile_SetBufSize(f, 0);
                         /* We don't care about these pipes anymore, so close them. */
                         CloseHandle(hChildStdoutRdDup);
                         CloseHandle(hChildStderrRdDup);
                         break;
                 }
                 file_count = 1;
                 break;

         case POPEN_2:
         case POPEN_4:
         {
                 char *m1, *m2;
                 PyObject *p1, *p2;

                 if (mode & _O_TEXT) {
                         m1 = "r";
                         m2 = "w";
                 } else {
                         m1 = "rb";
                         m2 = "wb";
                 }

                 fd1 = _open_osfhandle((Py_intptr_t)hChildStdinWrDup, mode);
                 f1 = _fdopen(fd1, m2);
                 fd2 = _open_osfhandle((Py_intptr_t)hChildStdoutRdDup, mode);
                 f2 = _fdopen(fd2, m1);
                 p1 = PyFile_FromFile(f1, cmdstring, m2, _PyPclose);
                 PyFile_SetBufSize(p1, 0);
                 p2 = PyFile_FromFile(f2, cmdstring, m1, _PyPclose);
                 PyFile_SetBufSize(p2, 0);

                 if (n != 4)
                         CloseHandle(hChildStderrRdDup);

                 f = PyTuple_Pack(2,p1,p2);
                 Py_XDECREF(p1);
                 Py_XDECREF(p2);
                 file_count = 2;
                 break;
         }

         case POPEN_3:
         {
                 char *m1, *m2;
                 PyObject *p1, *p2, *p3;

                 if (mode & _O_TEXT) {
                         m1 = "r";
                         m2 = "w";
                 } else {
                         m1 = "rb";
                         m2 = "wb";
                 }

                 fd1 = _open_osfhandle((Py_intptr_t)hChildStdinWrDup, mode);
                 f1 = _fdopen(fd1, m2);
                 fd2 = _open_osfhandle((Py_intptr_t)hChildStdoutRdDup, mode);
                 f2 = _fdopen(fd2, m1);
                 fd3 = _open_osfhandle((Py_intptr_t)hChildStderrRdDup, mode);
                 f3 = _fdopen(fd3, m1);
                 p1 = PyFile_FromFile(f1, cmdstring, m2, _PyPclose);
                 p2 = PyFile_FromFile(f2, cmdstring, m1, _PyPclose);
                 p3 = PyFile_FromFile(f3, cmdstring, m1, _PyPclose);
                 PyFile_SetBufSize(p1, 0);
                 PyFile_SetBufSize(p2, 0);
                 PyFile_SetBufSize(p3, 0);
                 f = PyTuple_Pack(3,p1,p2,p3);
                 Py_XDECREF(p1);
                 Py_XDECREF(p2);
                 Py_XDECREF(p3);
                 file_count = 3;
                 break;
         }
         }

         if (n == POPEN_4) {
                 if (!_PyPopenCreateProcess(cmdstring,
                                            hChildStdinRd,
                                            hChildStdoutWr,
                                            hChildStdoutWr,
                                            &hProcess))
                         return NULL;
         }
         else {
                 if (!_PyPopenCreateProcess(cmdstring,
                                            hChildStdinRd,
                                            hChildStdoutWr,
                                            hChildStderrWr,
                                            &hProcess))
                         return NULL;
         }

         /*
          * Insert the files we've created into the process dictionary
          * all referencing the list with the process handle and the
          * initial number of files (see description below in _PyPclose).
          * Since if _PyPclose later tried to wait on a process when all
          * handles weren't closed, it could create a deadlock with the
          * child, we spend some energy here to try to ensure that we
          * either insert all file handles into the dictionary or none
          * at all.  It's a little clumsy with the various popen modes
          * and variable number of files involved.
          */
         if (!_PyPopenProcs) {
                 _PyPopenProcs = PyDict_New();
         }

         if (_PyPopenProcs) {
                 PyObject *procObj, *hProcessObj, *intObj, *fileObj[3];
                 int ins_rc[3];

                 fileObj[0] = fileObj[1] = fileObj[2] = NULL;
                 ins_rc[0]  = ins_rc[1]  = ins_rc[2]  = 0;

                 procObj = PyList_New(2);
                 hProcessObj = PyLong_FromVoidPtr(hProcess);
                 intObj = PyInt_FromLong(file_count);

                 if (procObj && hProcessObj && intObj) {
                         PyList_SetItem(procObj,0,hProcessObj);
                         PyList_SetItem(procObj,1,intObj);

                         fileObj[0] = PyLong_FromVoidPtr(f1);
                         if (fileObj[0]) {
                            ins_rc[0] = PyDict_SetItem(_PyPopenProcs,
                                                       fileObj[0],
                                                       procObj);
                         }
                         if (file_count >= 2) {
                                 fileObj[1] = PyLong_FromVoidPtr(f2);
                                 if (fileObj[1]) {
                                    ins_rc[1] = PyDict_SetItem(_PyPopenProcs,
                                                               fileObj[1],
                                                               procObj);
                                 }
                         }
                         if (file_count >= 3) {
                                 fileObj[2] = PyLong_FromVoidPtr(f3);
                                 if (fileObj[2]) {
                                    ins_rc[2] = PyDict_SetItem(_PyPopenProcs,
                                                               fileObj[2],
                                                               procObj);
                                 }
                         }

                         if (ins_rc[0] < 0 || !fileObj[0] ||
                             ins_rc[1] < 0 || (file_count > 1 && !fileObj[1]) ||
                             ins_rc[2] < 0 || (file_count > 2 && !fileObj[2])) {
                                 /* Something failed - remove any dictionary
                                  * entries that did make it.
                                  */
                                 if (!ins_rc[0] && fileObj[0]) {
                                         PyDict_DelItem(_PyPopenProcs,
                                                        fileObj[0]);
                                 }
                                 if (!ins_rc[1] && fileObj[1]) {
                                         PyDict_DelItem(_PyPopenProcs,
                                                        fileObj[1]);
                                 }
                                 if (!ins_rc[2] && fileObj[2]) {
                                         PyDict_DelItem(_PyPopenProcs,
                                                        fileObj[2]);
                                 }
                         }
                 }

                 /*
                  * Clean up our localized references for the dictionary keys
                  * and value since PyDict_SetItem will Py_INCREF any copies
                  * that got placed in the dictionary.
                  */
                 Py_XDECREF(procObj);
                 Py_XDECREF(fileObj[0]);
                 Py_XDECREF(fileObj[1]);
                 Py_XDECREF(fileObj[2]);
         }

         /* Child is launched. Close the parents copy of those pipe
          * handles that only the child should have open.  You need to
          * make sure that no handles to the write end of the output pipe
          * are maintained in this process or else the pipe will not close
          * when the child process exits and the ReadFile will hang. */

         if (!CloseHandle(hChildStdinRd))
                 return win32_error("CloseHandle", NULL);

         if (!CloseHandle(hChildStdoutWr))
                 return win32_error("CloseHandle", NULL);

         if ((n != 4) && (!CloseHandle(hChildStderrWr)))
                 return win32_error("CloseHandle", NULL);

         return f;
}

/*
 * Wrapper for fclose() to use for popen* files, so we can retrieve the
 * exit code for the child process and return as a result of the close.
 *
 * This function uses the _PyPopenProcs dictionary in order to map the
 * input file pointer to information about the process that was
 * originally created by the popen* call that created the file pointer.
 * The dictionary uses the file pointer as a key (with one entry
 * inserted for each file returned by the original popen* call) and a
 * single list object as the value for all files from a single call.
 * The list object contains the Win32 process handle at [0], and a file
 * count at [1], which is initialized to the total number of file
 * handles using that list.
 *
 * This function closes whichever handle it is passed, and decrements
 * the file count in the dictionary for the process handle pointed to
 * by this file.  On the last close (when the file count reaches zero),
 * this function will wait for the child process and then return its
 * exit code as the result of the close() operation.  This permits the
 * files to be closed in any order - it is always the close() of the
 * final handle that will return the exit code.
 *
 * NOTE: This function is currently called with the GIL released.
 * hence we use the GILState API to manage our state.
 */

static int _PyPclose(FILE *file)
{
        int result;
        DWORD exit_code;
        HANDLE hProcess;
        PyObject *procObj, *hProcessObj, *intObj, *fileObj;
        long file_count;
#ifdef WITH_THREAD
        PyGILState_STATE state;
#endif

        /* Close the file handle first, to ensure it can't block the
         * child from exiting if it's the last handle.
         */
        result = fclose(file);
#ifdef WITH_THREAD
        state = PyGILState_Ensure();
#endif
        if (_PyPopenProcs) {
                if ((fileObj = PyLong_FromVoidPtr(file)) != NULL &&
                    (procObj = PyDict_GetItem(_PyPopenProcs,
                                              fileObj)) != NULL &&
                    (hProcessObj = PyList_GetItem(procObj,0)) != NULL &&
                    (intObj = PyList_GetItem(procObj,1)) != NULL) {

                        hProcess = PyLong_AsVoidPtr(hProcessObj);
                        file_count = PyInt_AsLong(intObj);

                        if (file_count > 1) {
                                /* Still other files referencing process */
                                file_count--;
                                PyList_SetItem(procObj,1,
                                               PyInt_FromLong(file_count));
                        } else {
                                /* Last file for this process */
                                if (result != EOF &&
                                    WaitForSingleObject(hProcess, INFINITE) != WAIT_FAILED &&
                                    GetExitCodeProcess(hProcess, &exit_code)) {
                                        /* Possible truncation here in 16-bit environments, but
                                         * real exit codes are just the lower byte in any event.
                                         */
                                        result = exit_code;
                                } else {
                                        /* Indicate failure - this will cause the file object
                                         * to raise an I/O error and translate the last Win32
                                         * error code from errno.  We do have a problem with
                                         * last errors that overlap the normal errno table,
                                         * but that's a consistent problem with the file object.
                                         */
                                        if (result != EOF) {
                                                /* If the error wasn't from the fclose(), then
                                                 * set errno for the file object error handling.
                                                 */
                                                errno = GetLastError();
                                        }
                                        result = -1;
                                }

                                /* Free up the native handle at this point */
                                CloseHandle(hProcess);
                        }

                        /* Remove this file pointer from dictionary */
                        PyDict_DelItem(_PyPopenProcs, fileObj);

                        if (PyDict_Size(_PyPopenProcs) == 0) {
                                Py_DECREF(_PyPopenProcs);
                                _PyPopenProcs = NULL;
                        }

                } /* if object retrieval ok */

                Py_XDECREF(fileObj);
        } /* if _PyPopenProcs */

#ifdef WITH_THREAD
        PyGILState_Release(state);
#endif
        return result;
}

#else /* which OS? */
static PyObject *
posix_popen(PyObject *self, PyObject *args)
{
        char *name;
        char *mode = "r";
        int bufsize = -1;
        FILE *fp;
        PyObject *f;
        if (!PyArg_ParseTuple(args, "s|si:popen", &name, &mode, &bufsize))
                return NULL;
        /* Strip mode of binary or text modifiers */
        if (strcmp(mode, "rb") == 0 || strcmp(mode, "rt") == 0)
                mode = "r";
        else if (strcmp(mode, "wb") == 0 || strcmp(mode, "wt") == 0)
                mode = "w";
        Py_BEGIN_ALLOW_THREADS
        fp = popen(name, mode);
        Py_END_ALLOW_THREADS
        if (fp == NULL)
                return posix_error();
        f = PyFile_FromFile(fp, name, mode, pclose);
        if (f != NULL)
                PyFile_SetBufSize(f, bufsize);
        return f;
}

#endif /* PYOS_??? */
#endif /* HAVE_POPEN */


#ifdef HAVE_SETUID
PyDoc_STRVAR(posix_setuid__doc__,
"setuid(uid)\n\n\
Set the current process's user id.");

static PyObject *
posix_setuid(PyObject *self, PyObject *args)
{
        int uid;
        if (!PyArg_ParseTuple(args, "i:setuid", &uid))
                return NULL;
        if (setuid(uid) < 0)
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}
#endif /* HAVE_SETUID */


#ifdef HAVE_SETEUID
PyDoc_STRVAR(posix_seteuid__doc__,
"seteuid(uid)\n\n\
Set the current process's effective user id.");

static PyObject *
posix_seteuid (PyObject *self, PyObject *args)
{
        int euid;
        if (!PyArg_ParseTuple(args, "i", &euid)) {
                return NULL;
        } else if (seteuid(euid) < 0) {
                return posix_error();
        } else {
                Py_INCREF(Py_None);
                return Py_None;
        }
}
#endif /* HAVE_SETEUID */

#ifdef HAVE_SETEGID
PyDoc_STRVAR(posix_setegid__doc__,
"setegid(gid)\n\n\
Set the current process's effective group id.");

static PyObject *
posix_setegid (PyObject *self, PyObject *args)
{
        int egid;
        if (!PyArg_ParseTuple(args, "i", &egid)) {
                return NULL;
        } else if (setegid(egid) < 0) {
                return posix_error();
        } else {
                Py_INCREF(Py_None);
                return Py_None;
        }
}
#endif /* HAVE_SETEGID */

#ifdef HAVE_SETREUID
PyDoc_STRVAR(posix_setreuid__doc__,
"setreuid(ruid, euid)\n\n\
Set the current process's real and effective user ids.");

static PyObject *
posix_setreuid (PyObject *self, PyObject *args)
{
        int ruid, euid;
        if (!PyArg_ParseTuple(args, "ii", &ruid, &euid)) {
                return NULL;
        } else if (setreuid(ruid, euid) < 0) {
                return posix_error();
        } else {
                Py_INCREF(Py_None);
                return Py_None;
        }
}
#endif /* HAVE_SETREUID */

#ifdef HAVE_SETREGID
PyDoc_STRVAR(posix_setregid__doc__,
"setregid(rgid, egid)\n\n\
Set the current process's real and effective group ids.");

static PyObject *
posix_setregid (PyObject *self, PyObject *args)
{
        int rgid, egid;
        if (!PyArg_ParseTuple(args, "ii", &rgid, &egid)) {
                return NULL;
        } else if (setregid(rgid, egid) < 0) {
                return posix_error();
        } else {
                Py_INCREF(Py_None);
                return Py_None;
        }
}
#endif /* HAVE_SETREGID */

#ifdef HAVE_SETGID
PyDoc_STRVAR(posix_setgid__doc__,
"setgid(gid)\n\n\
Set the current process's group id.");

static PyObject *
posix_setgid(PyObject *self, PyObject *args)
{
        int gid;
        if (!PyArg_ParseTuple(args, "i:setgid", &gid))
                return NULL;
        if (setgid(gid) < 0)
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}
#endif /* HAVE_SETGID */

#ifdef HAVE_SETGROUPS
PyDoc_STRVAR(posix_setgroups__doc__,
"setgroups(list)\n\n\
Set the groups of the current process to list.");

static PyObject *
posix_setgroups(PyObject *self, PyObject *groups)
{
        int i, len;
        gid_t grouplist[MAX_GROUPS];

        if (!PySequence_Check(groups)) {
                PyErr_SetString(PyExc_TypeError, "setgroups argument must be a sequence");
                return NULL;
        }
        len = PySequence_Size(groups);
        if (len > MAX_GROUPS) {
                PyErr_SetString(PyExc_ValueError, "too many groups");
                return NULL;
        }
        for(i = 0; i < len; i++) {
                PyObject *elem;
                elem = PySequence_GetItem(groups, i);
                if (!elem)
                        return NULL;
                if (!PyInt_Check(elem)) {
                        if (!PyLong_Check(elem)) {
                                PyErr_SetString(PyExc_TypeError,
                                                "groups must be integers");
                                Py_DECREF(elem);
                                return NULL;
                        } else {
                                unsigned long x = PyLong_AsUnsignedLong(elem);
                                if (PyErr_Occurred()) {
                                        PyErr_SetString(PyExc_TypeError, 
                                                        "group id too big");
                                        Py_DECREF(elem);
                                        return NULL;
                                }
                                grouplist[i] = x;
                                /* read back the value to see if it fitted in gid_t */
                                if (grouplist[i] != x) {
                                        PyErr_SetString(PyExc_TypeError,
                                                        "group id too big");
                                        Py_DECREF(elem);
                                        return NULL;
                                }
                        }
                } else {
                        long x  = PyInt_AsLong(elem);
                        grouplist[i] = x;
                        if (grouplist[i] != x) {
                                PyErr_SetString(PyExc_TypeError,
                                                "group id too big");
                                Py_DECREF(elem);
                                return NULL;
                        }
                }
                Py_DECREF(elem);
        }

        if (setgroups(len, grouplist) < 0)
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}
#endif /* HAVE_SETGROUPS */

#if defined(HAVE_WAIT3) || defined(HAVE_WAIT4)
static PyObject *
wait_helper(int pid, int status, struct rusage *ru)
{
        PyObject *result;
        static PyObject *struct_rusage;

        if (pid == -1)
                return posix_error();

        if (struct_rusage == NULL) {
                PyObject *m = PyImport_ImportModule("resource");
                if (m == NULL)
                        return NULL;
                struct_rusage = PyObject_GetAttrString(m, "struct_rusage");
                Py_DECREF(m);
                if (struct_rusage == NULL)
                        return NULL;
        }

        /* XXX(nnorwitz): Copied (w/mods) from resource.c, there should be only one. */
        result = PyStructSequence_New((PyTypeObject*) struct_rusage);
        if (!result)
                return NULL;

#ifndef doubletime
#define doubletime(TV) ((double)(TV).tv_sec + (TV).tv_usec * 0.000001)
#endif

        PyStructSequence_SET_ITEM(result, 0,
                        PyFloat_FromDouble(doubletime(ru->ru_utime)));
        PyStructSequence_SET_ITEM(result, 1,
                        PyFloat_FromDouble(doubletime(ru->ru_stime)));
#define SET_INT(result, index, value)\
                PyStructSequence_SET_ITEM(result, index, PyInt_FromLong(value))
        SET_INT(result, 2, ru->ru_maxrss);
        SET_INT(result, 3, ru->ru_ixrss);
        SET_INT(result, 4, ru->ru_idrss);
        SET_INT(result, 5, ru->ru_isrss);
        SET_INT(result, 6, ru->ru_minflt);
        SET_INT(result, 7, ru->ru_majflt);
        SET_INT(result, 8, ru->ru_nswap);
        SET_INT(result, 9, ru->ru_inblock);
        SET_INT(result, 10, ru->ru_oublock);
        SET_INT(result, 11, ru->ru_msgsnd);
        SET_INT(result, 12, ru->ru_msgrcv);
        SET_INT(result, 13, ru->ru_nsignals);
        SET_INT(result, 14, ru->ru_nvcsw);
        SET_INT(result, 15, ru->ru_nivcsw);
#undef SET_INT

        if (PyErr_Occurred()) {
                Py_DECREF(result);
                return NULL;
        }

        return Py_BuildValue("iiN", pid, status, result);
}
#endif /* HAVE_WAIT3 || HAVE_WAIT4 */

#ifdef HAVE_WAIT3
PyDoc_STRVAR(posix_wait3__doc__,
"wait3(options) -> (pid, status, rusage)\n\n\
Wait for completion of a child process.");

static PyObject *
posix_wait3(PyObject *self, PyObject *args)
{
        int pid, options;
        struct rusage ru;
        WAIT_TYPE status;
        WAIT_STATUS_INT(status) = 0;

        if (!PyArg_ParseTuple(args, "i:wait3", &options))
                return NULL;

        Py_BEGIN_ALLOW_THREADS
        pid = wait3(&status, options, &ru);
        Py_END_ALLOW_THREADS

        return wait_helper(pid, WAIT_STATUS_INT(status), &ru);
}
#endif /* HAVE_WAIT3 */

#ifdef HAVE_WAIT4
PyDoc_STRVAR(posix_wait4__doc__,
"wait4(pid, options) -> (pid, status, rusage)\n\n\
Wait for completion of a given child process.");

static PyObject *
posix_wait4(PyObject *self, PyObject *args)
{
        int pid, options;
        struct rusage ru;
        WAIT_TYPE status;
        WAIT_STATUS_INT(status) = 0;

        if (!PyArg_ParseTuple(args, "ii:wait4", &pid, &options))
                return NULL;

        Py_BEGIN_ALLOW_THREADS
        pid = wait4(pid, &status, options, &ru);
        Py_END_ALLOW_THREADS

        return wait_helper(pid, WAIT_STATUS_INT(status), &ru);
}
#endif /* HAVE_WAIT4 */

#ifdef HAVE_WAITPID
PyDoc_STRVAR(posix_waitpid__doc__,
"waitpid(pid, options) -> (pid, status)\n\n\
Wait for completion of a given child process.");

static PyObject *
posix_waitpid(PyObject *self, PyObject *args)
{
        int pid, options;
        WAIT_TYPE status;
        WAIT_STATUS_INT(status) = 0;

        if (!PyArg_ParseTuple(args, "ii:waitpid", &pid, &options))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        pid = waitpid(pid, &status, options);
        Py_END_ALLOW_THREADS
        if (pid == -1)
                return posix_error();

        return Py_BuildValue("ii", pid, WAIT_STATUS_INT(status));
}

#elif defined(HAVE_CWAIT)

/* MS C has a variant of waitpid() that's usable for most purposes. */
PyDoc_STRVAR(posix_waitpid__doc__,
"waitpid(pid, options) -> (pid, status << 8)\n\n"
"Wait for completion of a given process.  options is ignored on Windows.");

static PyObject *
posix_waitpid(PyObject *self, PyObject *args)
{
        Py_intptr_t pid;
        int status, options;

        if (!PyArg_ParseTuple(args, "ii:waitpid", &pid, &options))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        pid = _cwait(&status, pid, options);
        Py_END_ALLOW_THREADS
        if (pid == -1)
                return posix_error();

        /* shift the status left a byte so this is more like the POSIX waitpid */
        return Py_BuildValue("ii", pid, status << 8);
}
#endif /* HAVE_WAITPID || HAVE_CWAIT */

#ifdef HAVE_WAIT
PyDoc_STRVAR(posix_wait__doc__,
"wait() -> (pid, status)\n\n\
Wait for completion of a child process.");

static PyObject *
posix_wait(PyObject *self, PyObject *noargs)
{
        int pid;
        WAIT_TYPE status;
        WAIT_STATUS_INT(status) = 0;

        Py_BEGIN_ALLOW_THREADS
        pid = wait(&status);
        Py_END_ALLOW_THREADS
        if (pid == -1)
                return posix_error();

        return Py_BuildValue("ii", pid, WAIT_STATUS_INT(status));
}
#endif


PyDoc_STRVAR(posix_lstat__doc__,
"lstat(path) -> stat result\n\n\
Like stat(path), but do not follow symbolic links.");

static PyObject *
posix_lstat(PyObject *self, PyObject *args)
{
#ifdef HAVE_LSTAT
        return posix_do_stat(self, args, "et:lstat", lstat, NULL, NULL);
#else /* !HAVE_LSTAT */
#ifdef MS_WINDOWS
        return posix_do_stat(self, args, "et:lstat", STAT, "U:lstat", win32_wstat);
#else
        return posix_do_stat(self, args, "et:lstat", STAT, NULL, NULL);
#endif
#endif /* !HAVE_LSTAT */
}


#ifdef HAVE_READLINK
PyDoc_STRVAR(posix_readlink__doc__,
"readlink(path) -> path\n\n\
Return a string representing the path to which the symbolic link points.");

static PyObject *
posix_readlink(PyObject *self, PyObject *args)
{
        char buf[MAXPATHLEN];
        char *path;
        int n;
        if (!PyArg_ParseTuple(args, "s:readlink", &path))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        n = readlink(path, buf, (int) sizeof buf);
        Py_END_ALLOW_THREADS
        if (n < 0)
                return posix_error_with_filename(path);
        return PyString_FromStringAndSize(buf, n);
}
#endif /* HAVE_READLINK */


#ifdef HAVE_SYMLINK
PyDoc_STRVAR(posix_symlink__doc__,
"symlink(src, dst)\n\n\
Create a symbolic link pointing to src named dst.");

static PyObject *
posix_symlink(PyObject *self, PyObject *args)
{
        return posix_2str(args, "etet:symlink", symlink);
}
#endif /* HAVE_SYMLINK */


#ifdef HAVE_TIMES
#ifndef HZ
#define HZ 60 /* Universal constant :-) */
#endif /* HZ */

#if defined(PYCC_VACPP) && defined(PYOS_OS2)
static long
system_uptime(void)
{
    ULONG     value = 0;

    Py_BEGIN_ALLOW_THREADS
    DosQuerySysInfo(QSV_MS_COUNT, QSV_MS_COUNT, &value, sizeof(value));
    Py_END_ALLOW_THREADS

    return value;
}

static PyObject *
posix_times(PyObject *self, PyObject *noargs)
{
    /* Currently Only Uptime is Provided -- Others Later */
        return Py_BuildValue("ddddd",
                             (double)0 /* t.tms_utime / HZ */,
                             (double)0 /* t.tms_stime / HZ */,
                             (double)0 /* t.tms_cutime / HZ */,
                             (double)0 /* t.tms_cstime / HZ */,
                             (double)system_uptime() / 1000);
}
#else /* not OS2 */
static PyObject *
posix_times(PyObject *self, PyObject *noargs)
{
        struct tms t;
        clock_t c;
        errno = 0;
        c = times(&t);
        if (c == (clock_t) -1)
                return posix_error();
        return Py_BuildValue("ddddd",
                             (double)t.tms_utime / HZ,
                             (double)t.tms_stime / HZ,
                             (double)t.tms_cutime / HZ,
                             (double)t.tms_cstime / HZ,
                             (double)c / HZ);
}
#endif /* not OS2 */
#endif /* HAVE_TIMES */


#ifdef MS_WINDOWS
#define HAVE_TIMES      /* so the method table will pick it up */
static PyObject *
posix_times(PyObject *self, PyObject *noargs)
{
        FILETIME create, exit, kernel, user;
        HANDLE hProc;
        hProc = GetCurrentProcess();
        GetProcessTimes(hProc, &create, &exit, &kernel, &user);
        /* The fields of a FILETIME structure are the hi and lo part
           of a 64-bit value expressed in 100 nanosecond units.
           1e7 is one second in such units; 1e-7 the inverse.
           429.4967296 is 2**32 / 1e7 or 2**32 * 1e-7.
        */
        return Py_BuildValue(
                "ddddd",
                (double)(kernel.dwHighDateTime*429.4967296 +
                         kernel.dwLowDateTime*1e-7),
                (double)(user.dwHighDateTime*429.4967296 +
                         user.dwLowDateTime*1e-7),
                (double)0,
                (double)0,
                (double)0);
}
#endif /* MS_WINDOWS */

#ifdef HAVE_TIMES
PyDoc_STRVAR(posix_times__doc__,
"times() -> (utime, stime, cutime, cstime, elapsed_time)\n\n\
Return a tuple of floating point numbers indicating process times.");
#endif


#ifdef HAVE_GETSID
PyDoc_STRVAR(posix_getsid__doc__,
"getsid(pid) -> sid\n\n\
Call the system call getsid().");

static PyObject *
posix_getsid(PyObject *self, PyObject *args)
{
        int pid, sid;
        if (!PyArg_ParseTuple(args, "i:getsid", &pid))
                return NULL;
        sid = getsid(pid);
        if (sid < 0)
                return posix_error();
        return PyInt_FromLong((long)sid);
}
#endif /* HAVE_GETSID */


#ifdef HAVE_SETSID
PyDoc_STRVAR(posix_setsid__doc__,
"setsid()\n\n\
Call the system call setsid().");

static PyObject *
posix_setsid(PyObject *self, PyObject *noargs)
{
        if (setsid() < 0)
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}
#endif /* HAVE_SETSID */

#ifdef HAVE_SETPGID
PyDoc_STRVAR(posix_setpgid__doc__,
"setpgid(pid, pgrp)\n\n\
Call the system call setpgid().");

static PyObject *
posix_setpgid(PyObject *self, PyObject *args)
{
        int pid, pgrp;
        if (!PyArg_ParseTuple(args, "ii:setpgid", &pid, &pgrp))
                return NULL;
        if (setpgid(pid, pgrp) < 0)
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}
#endif /* HAVE_SETPGID */


#ifdef HAVE_TCGETPGRP
PyDoc_STRVAR(posix_tcgetpgrp__doc__,
"tcgetpgrp(fd) -> pgid\n\n\
Return the process group associated with the terminal given by a fd.");

static PyObject *
posix_tcgetpgrp(PyObject *self, PyObject *args)
{
        int fd, pgid;
        if (!PyArg_ParseTuple(args, "i:tcgetpgrp", &fd))
                return NULL;
        pgid = tcgetpgrp(fd);
        if (pgid < 0)
                return posix_error();
        return PyInt_FromLong((long)pgid);
}
#endif /* HAVE_TCGETPGRP */


#ifdef HAVE_TCSETPGRP
PyDoc_STRVAR(posix_tcsetpgrp__doc__,
"tcsetpgrp(fd, pgid)\n\n\
Set the process group associated with the terminal given by a fd.");

static PyObject *
posix_tcsetpgrp(PyObject *self, PyObject *args)
{
        int fd, pgid;
        if (!PyArg_ParseTuple(args, "ii:tcsetpgrp", &fd, &pgid))
                return NULL;
        if (tcsetpgrp(fd, pgid) < 0)
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}
#endif /* HAVE_TCSETPGRP */

/* Functions acting on file descriptors */

PyDoc_STRVAR(posix_open__doc__,
"open(filename, flag [, mode=0777]) -> fd\n\n\
Open a file (for low level IO).");

static PyObject *
posix_open(PyObject *self, PyObject *args)
{
        char *file = NULL;
        int flag;
        int mode = 0777;
        int fd;

#ifdef MS_WINDOWS
        if (unicode_file_names()) {
                PyUnicodeObject *po;
                if (PyArg_ParseTuple(args, "Ui|i:mkdir", &po, &flag, &mode)) {
                        Py_BEGIN_ALLOW_THREADS
                        /* PyUnicode_AS_UNICODE OK without thread
                           lock as it is a simple dereference. */
                        fd = _wopen(PyUnicode_AS_UNICODE(po), flag, mode);
                        Py_END_ALLOW_THREADS
                        if (fd < 0)
                                return posix_error();
                        return PyInt_FromLong((long)fd);
                }
                /* Drop the argument parsing error as narrow strings
                   are also valid. */
                PyErr_Clear();
        }
#endif

        if (!PyArg_ParseTuple(args, "eti|i",
                              Py_FileSystemDefaultEncoding, &file,
                              &flag, &mode))
                return NULL;

        Py_BEGIN_ALLOW_THREADS
        fd = open(file, flag, mode);
        Py_END_ALLOW_THREADS
        if (fd < 0)
                return posix_error_with_allocated_filename(file);
        PyMem_Free(file);
        return PyInt_FromLong((long)fd);
}


PyDoc_STRVAR(posix_close__doc__,
"close(fd)\n\n\
Close a file descriptor (for low level IO).");

static PyObject *
posix_close(PyObject *self, PyObject *args)
{
        int fd, res;
        if (!PyArg_ParseTuple(args, "i:close", &fd))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        res = close(fd);
        Py_END_ALLOW_THREADS
        if (res < 0)
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}


PyDoc_STRVAR(posix_dup__doc__,
"dup(fd) -> fd2\n\n\
Return a duplicate of a file descriptor.");

static PyObject *
posix_dup(PyObject *self, PyObject *args)
{
        int fd;
        if (!PyArg_ParseTuple(args, "i:dup", &fd))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        fd = dup(fd);
        Py_END_ALLOW_THREADS
        if (fd < 0)
                return posix_error();
        return PyInt_FromLong((long)fd);
}


PyDoc_STRVAR(posix_dup2__doc__,
"dup2(old_fd, new_fd)\n\n\
Duplicate file descriptor.");

static PyObject *
posix_dup2(PyObject *self, PyObject *args)
{
        int fd, fd2, res;
        if (!PyArg_ParseTuple(args, "ii:dup2", &fd, &fd2))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        res = dup2(fd, fd2);
        Py_END_ALLOW_THREADS
        if (res < 0)
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}


PyDoc_STRVAR(posix_lseek__doc__,
"lseek(fd, pos, how) -> newpos\n\n\
Set the current position of a file descriptor.");

static PyObject *
posix_lseek(PyObject *self, PyObject *args)
{
        int fd, how;
#if defined(MS_WIN64) || defined(MS_WINDOWS)
        PY_LONG_LONG pos, res;
#else
        off_t pos, res;
#endif
        PyObject *posobj;
        if (!PyArg_ParseTuple(args, "iOi:lseek", &fd, &posobj, &how))
                return NULL;
#ifdef SEEK_SET
        /* Turn 0, 1, 2 into SEEK_{SET,CUR,END} */
        switch (how) {
        case 0: how = SEEK_SET; break;
        case 1: how = SEEK_CUR; break;
        case 2: how = SEEK_END; break;
        }
#endif /* SEEK_END */

#if !defined(HAVE_LARGEFILE_SUPPORT)
        pos = PyInt_AsLong(posobj);
#else
        pos = PyLong_Check(posobj) ?
                PyLong_AsLongLong(posobj) : PyInt_AsLong(posobj);
#endif
        if (PyErr_Occurred())
                return NULL;

        Py_BEGIN_ALLOW_THREADS
#if defined(MS_WIN64) || defined(MS_WINDOWS)
        res = _lseeki64(fd, pos, how);
#else
        res = lseek(fd, pos, how);
#endif
        Py_END_ALLOW_THREADS
        if (res < 0)
                return posix_error();

#if !defined(HAVE_LARGEFILE_SUPPORT)
        return PyInt_FromLong(res);
#else
        return PyLong_FromLongLong(res);
#endif
}


PyDoc_STRVAR(posix_read__doc__,
"read(fd, buffersize) -> string\n\n\
Read a file descriptor.");

static PyObject *
posix_read(PyObject *self, PyObject *args)
{
        int fd, size, n;
        PyObject *buffer;
        if (!PyArg_ParseTuple(args, "ii:read", &fd, &size))
                return NULL;
        if (size < 0) {
                errno = EINVAL;
                return posix_error();
        }
        buffer = PyString_FromStringAndSize((char *)NULL, size);
        if (buffer == NULL)
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        n = read(fd, PyString_AsString(buffer), size);
        Py_END_ALLOW_THREADS
        if (n < 0) {
                Py_DECREF(buffer);
                return posix_error();
        }
        if (n != size)
                _PyString_Resize(&buffer, n);
        return buffer;
}


PyDoc_STRVAR(posix_write__doc__,
"write(fd, string) -> byteswritten\n\n\
Write a string to a file descriptor.");

static PyObject *
posix_write(PyObject *self, PyObject *args)
{
        int fd;
        Py_ssize_t size;
        char *buffer;

        if (!PyArg_ParseTuple(args, "is#:write", &fd, &buffer, &size))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        size = write(fd, buffer, (size_t)size);
        Py_END_ALLOW_THREADS
        if (size < 0)
                return posix_error();
        return PyInt_FromSsize_t(size);
}


PyDoc_STRVAR(posix_fstat__doc__,
"fstat(fd) -> stat result\n\n\
Like stat(), but for an open file descriptor.");

static PyObject *
posix_fstat(PyObject *self, PyObject *args)
{
        int fd;
        STRUCT_STAT st;
        int res;
        if (!PyArg_ParseTuple(args, "i:fstat", &fd))
                return NULL;
#ifdef __VMS
        /* on OpenVMS we must ensure that all bytes are written to the file */
        fsync(fd);
#endif
        Py_BEGIN_ALLOW_THREADS
        res = FSTAT(fd, &st);
        Py_END_ALLOW_THREADS
        if (res != 0) {
#ifdef MS_WINDOWS
                return win32_error("fstat", NULL);
#else
                return posix_error();
#endif
        }

        return _pystat_fromstructstat(&st);
}


PyDoc_STRVAR(posix_fdopen__doc__,
"fdopen(fd [, mode='r' [, bufsize]]) -> file_object\n\n\
Return an open file object connected to a file descriptor.");

static PyObject *
posix_fdopen(PyObject *self, PyObject *args)
{
        int fd;
        char *mode = "r";
        int bufsize = -1;
        FILE *fp;
        PyObject *f;
        if (!PyArg_ParseTuple(args, "i|si", &fd, &mode, &bufsize))
                return NULL;

        if (mode[0] != 'r' && mode[0] != 'w' && mode[0] != 'a') {
                PyErr_Format(PyExc_ValueError,
                             "invalid file mode '%s'", mode);
                return NULL;
        }
        Py_BEGIN_ALLOW_THREADS
#if !defined(MS_WINDOWS) && defined(HAVE_FCNTL_H)
        if (mode[0] == 'a') {
                /* try to make sure the O_APPEND flag is set */
                int flags;
                flags = fcntl(fd, F_GETFL);
                if (flags != -1)
                        fcntl(fd, F_SETFL, flags | O_APPEND);
                fp = fdopen(fd, mode);
                if (fp == NULL && flags != -1)
                        /* restore old mode if fdopen failed */
                        fcntl(fd, F_SETFL, flags);
        } else {
                fp = fdopen(fd, mode);
        }
#else
        fp = fdopen(fd, mode);
#endif
        Py_END_ALLOW_THREADS
        if (fp == NULL)
                return posix_error();
        f = PyFile_FromFile(fp, "<fdopen>", mode, fclose);
        if (f != NULL)
                PyFile_SetBufSize(f, bufsize);
        return f;
}

PyDoc_STRVAR(posix_isatty__doc__,
"isatty(fd) -> bool\n\n\
Return True if the file descriptor 'fd' is an open file descriptor\n\
connected to the slave end of a terminal.");

static PyObject *
posix_isatty(PyObject *self, PyObject *args)
{
        int fd;
        if (!PyArg_ParseTuple(args, "i:isatty", &fd))
                return NULL;
        return PyBool_FromLong(isatty(fd));
}

#ifdef HAVE_PIPE
PyDoc_STRVAR(posix_pipe__doc__,
"pipe() -> (read_end, write_end)\n\n\
Create a pipe.");

static PyObject *
posix_pipe(PyObject *self, PyObject *noargs)
{
#if defined(PYOS_OS2)
    HFILE read, write;
    APIRET rc;

        Py_BEGIN_ALLOW_THREADS
    rc = DosCreatePipe( &read, &write, 4096);
        Py_END_ALLOW_THREADS
    if (rc != NO_ERROR)
        return os2_error(rc);

    return Py_BuildValue("(ii)", read, write);
#else
#if !defined(MS_WINDOWS)
        int fds[2];
        int res;
        Py_BEGIN_ALLOW_THREADS
        res = pipe(fds);
        Py_END_ALLOW_THREADS
        if (res != 0)
                return posix_error();
        return Py_BuildValue("(ii)", fds[0], fds[1]);
#else /* MS_WINDOWS */
        HANDLE read, write;
        int read_fd, write_fd;
        BOOL ok;
        Py_BEGIN_ALLOW_THREADS
        ok = CreatePipe(&read, &write, NULL, 0);
        Py_END_ALLOW_THREADS
        if (!ok)
                return win32_error("CreatePipe", NULL);
        read_fd = _open_osfhandle((Py_intptr_t)read, 0);
        write_fd = _open_osfhandle((Py_intptr_t)write, 1);
        return Py_BuildValue("(ii)", read_fd, write_fd);
#endif /* MS_WINDOWS */
#endif
}
#endif  /* HAVE_PIPE */


#ifdef HAVE_MKFIFO
PyDoc_STRVAR(posix_mkfifo__doc__,
"mkfifo(filename [, mode=0666])\n\n\
Create a FIFO (a POSIX named pipe).");

static PyObject *
posix_mkfifo(PyObject *self, PyObject *args)
{
        char *filename;
        int mode = 0666;
        int res;
        if (!PyArg_ParseTuple(args, "s|i:mkfifo", &filename, &mode))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        res = mkfifo(filename, mode);
        Py_END_ALLOW_THREADS
        if (res < 0)
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}
#endif


#if defined(HAVE_MKNOD) && defined(HAVE_MAKEDEV)
PyDoc_STRVAR(posix_mknod__doc__,
"mknod(filename [, mode=0600, device])\n\n\
Create a filesystem node (file, device special file or named pipe)\n\
named filename. mode specifies both the permissions to use and the\n\
type of node to be created, being combined (bitwise OR) with one of\n\
S_IFREG, S_IFCHR, S_IFBLK, and S_IFIFO. For S_IFCHR and S_IFBLK,\n\
device defines the newly created device special file (probably using\n\
os.makedev()), otherwise it is ignored.");


static PyObject *
posix_mknod(PyObject *self, PyObject *args)
{
        char *filename;
        int mode = 0600;
        int device = 0;
        int res;
        if (!PyArg_ParseTuple(args, "s|ii:mknod", &filename, &mode, &device))
                return NULL;
        Py_BEGIN_ALLOW_THREADS
        res = mknod(filename, mode, device);
        Py_END_ALLOW_THREADS
        if (res < 0)
                return posix_error();
        Py_INCREF(Py_None);
        return Py_None;
}
#endif

#ifdef HAVE_DEVICE_MACROS
PyDoc_STRVAR(posix_major__doc__,
"major(device) -> major number\n\
Extracts a device major number from a raw device number.");

static PyObject *
posix_major(PyObject *self, PyObject *args)
{
        int device;
        if (!PyArg_ParseTuple(args, "i:major", &device))
                return NULL;
        return PyInt_FromLong((long)major(device));
}

PyDoc_STRVAR(posix_minor__doc__,
"minor(device) -> minor number\n\
Extracts a device minor number from a raw device number.");

static PyObject *
posix_minor(PyObject *self, PyObject *args)
{
        int device;
        if (!PyArg_ParseTuple(args, "i:minor", &device))
                return NULL;
        return PyInt_FromLong((long)minor(device));
}

PyDoc_STRVAR(posix_makedev__doc__,
"makedev(major, minor) -> device number\n\
Composes a raw device number from the major and minor device numbers.");

static PyObject *
posix_makedev(PyObject *self, PyObject *args)
{
        int major, minor;
        if (!PyArg_ParseTuple(args, "ii:makedev", &major, &minor))
                return NULL;
        return PyInt_FromLong((long)makedev(major, minor));
}
#endif /* device macros */


#ifdef HAVE_FTRUNCATE
PyDoc_STRVAR(posix_ftruncate__doc__,
"ftruncate(fd, length)\n\n\
Truncate a file to a specified length.");

static PyObject *
posix_ftruncate(PyObject *self, PyObject *args)
{
        int fd;
        off_t length;
        int res;
        PyObject *lenobj;

        if (!PyArg_ParseTuple(args, "iO:ftruncate", &fd, &lenobj))
                return NULL;

#if !defined(HAVE_LARGEFILE_SUPPORT)
        length = PyInt_AsLong(lenobj);
#else
        length = PyLong_Check(lenobj) ?
                PyLong_AsLongLong(lenobj) : PyInt_AsLong(lenobj);
#endif
        if (PyErr_Occurred())
                return NULL;

        Py_BEGIN_ALLOW_THREADS
        res = ftruncate(fd, length);
        Py_END_ALLOW_THREADS
        if (res < 0) {
                PyErr_SetFromErrno(PyExc_IOError);
                return NULL;
        }
        Py_INCREF(Py_None);
        return Py_None;
}
#endif

#ifdef HAVE_PUTENV
PyDoc_STRVAR(posix_putenv__doc__,
"putenv(key, value)\n\n\
Change or add an environment variable.");

/* Save putenv() parameters as values here, so we can collect them when they
 * get re-set with another call for the same key. */
static PyObject *posix_putenv_garbage;

static PyObject *
posix_putenv(PyObject *self, PyObject *args)
{
        char *s1, *s2;
        char *newenv;
        PyObject *newstr;
        size_t len;

        if (!PyArg_ParseTuple(args, "ss:putenv", &s1, &s2))
                return NULL;

#if defined(PYOS_OS2)
    if (stricmp(s1, "BEGINLIBPATH") == 0) {
        APIRET rc;

        rc = DosSetExtLIBPATH(s2, BEGIN_LIBPATH);
        if (rc != NO_ERROR)
            return os2_error(rc);

    } else if (stricmp(s1, "ENDLIBPATH") == 0) {
        APIRET rc;

        rc = DosSetExtLIBPATH(s2, END_LIBPATH);
        if (rc != NO_ERROR)
            return os2_error(rc);
    } else {
#endif

        /* XXX This can leak memory -- not easy to fix :-( */
        len = strlen(s1) + strlen(s2) + 2;
        /* len includes space for a trailing \0; the size arg to
           PyString_FromStringAndSize does not count that */
        newstr = PyString_FromStringAndSize(NULL, (int)len - 1);
        if (newstr == NULL)
                return PyErr_NoMemory();
        newenv = PyString_AS_STRING(newstr);
        PyOS_snprintf(newenv, len, "%s=%s", s1, s2);
        if (putenv(newenv)) {
                Py_DECREF(newstr);
                posix_error();
                return NULL;
        }
        /* Install the first arg and newstr in posix_putenv_garbage;
         * this will cause previous value to be collected.  This has to
         * happen after the real putenv() call because the old value
         * was still accessible until then. */
        if (PyDict_SetItem(posix_putenv_garbage,
                           PyTuple_GET_ITEM(args, 0), newstr)) {
                /* really not much we can do; just leak */
                PyErr_Clear();
        }
        else {
                Py_DECREF(newstr);
        }

#if defined(PYOS_OS2)
    }
#endif
        Py_INCREF(Py_None);
        return Py_None;
}
#endif /* putenv */

#ifdef HAVE_UNSETENV
PyDoc_STRVAR(posix_unsetenv__doc__,
"unsetenv(key)\n\n\
Delete an environment variable.");

static PyObject *
posix_unsetenv(PyObject *self, PyObject *args)
{
        char *s1;

        if (!PyArg_ParseTuple(args, "s:unsetenv", &s1))
                return NULL;

        unsetenv(s1);

        /* Remove the key from posix_putenv_garbage;
         * this will cause it to be collected.  This has to
         * happen after the real unsetenv() call because the
         * old value was still accessible until then.
         */
        if (PyDict_DelItem(posix_putenv_garbage,
                PyTuple_GET_ITEM(args, 0))) {
                /* really not much we can do; just leak */
                PyErr_Clear();
        }

        Py_INCREF(Py_None);
        return Py_None;
}
#endif /* unsetenv */

#ifdef HAVE_STRERROR
PyDoc_STRVAR(posix_strerror__doc__,
"strerror(code) -> string\n\n\
Translate an error code to a message string.");

static PyObject *
posix_strerror(PyObject *self, PyObject *args)
{
        int code;
        char *message;
        if (!PyArg_ParseTuple(args, "i:strerror", &code))
                return NULL;
        message = strerror(code);
        if (message == NULL) {
                PyErr_SetString(PyExc_ValueError,
                                "strerror() argument out of range");
                return NULL;
        }
        return PyString_FromString(message);
}
#endif /* strerror */


#ifdef HAVE_SYS_WAIT_H

#ifdef WCOREDUMP
PyDoc_STRVAR(posix_WCOREDUMP__doc__,
"WCOREDUMP(status) -> bool\n\n\
Return True if the process returning 'status' was dumped to a core file.");

static PyObject *
posix_WCOREDUMP(PyObject *self, PyObject *args)
{
        WAIT_TYPE status;
        WAIT_STATUS_INT(status) = 0;

        if (!PyArg_ParseTuple(args, "i:WCOREDUMP", &WAIT_STATUS_INT(status)))
                return NULL;

        return PyBool_FromLong(WCOREDUMP(status));
}
#endif /* WCOREDUMP */

#ifdef WIFCONTINUED
PyDoc_STRVAR(posix_WIFCONTINUED__doc__,
"WIFCONTINUED(status) -> bool\n\n\
Return True if the process returning 'status' was continued from a\n\
job control stop.");

static PyObject *
posix_WIFCONTINUED(PyObject *self, PyObject *args)
{
        WAIT_TYPE status;
        WAIT_STATUS_INT(status) = 0;

        if (!PyArg_ParseTuple(args, "i:WCONTINUED", &WAIT_STATUS_INT(status)))
                return NULL;

        return PyBool_FromLong(WIFCONTINUED(status));
}
#endif /* WIFCONTINUED */

#ifdef WIFSTOPPED
PyDoc_STRVAR(posix_WIFSTOPPED__doc__,
"WIFSTOPPED(status) -> bool\n\n\
Return True if the process returning 'status' was stopped.");

static PyObject *
posix_WIFSTOPPED(PyObject *self, PyObject *args)
{
        WAIT_TYPE status;
        WAIT_STATUS_INT(status) = 0;

        if (!PyArg_ParseTuple(args, "i:WIFSTOPPED", &WAIT_STATUS_INT(status)))
                return NULL;

        return PyBool_FromLong(WIFSTOPPED(status));
}
#endif /* WIFSTOPPED */

#ifdef WIFSIGNALED
PyDoc_STRVAR(posix_WIFSIGNALED__doc__,
"WIFSIGNALED(status) -> bool\n\n\
Return True if the process returning 'status' was terminated by a signal.");

static PyObject *
posix_WIFSIGNALED(PyObject *self, PyObject *args)
{
        WAIT_TYPE status;
        WAIT_STATUS_INT(status) = 0;

        if (!PyArg_ParseTuple(args, "i:WIFSIGNALED", &WAIT_STATUS_INT(status)))
                return NULL;

        return PyBool_FromLong(WIFSIGNALED(status));
}
#endif /* WIFSIGNALED */

#ifdef WIFEXITED
PyDoc_STRVAR(posix_WIFEXITED__doc__,
"WIFEXITED(status) -> bool\n\n\
Return true if the process returning 'status' exited using the exit()\n\
system call.");

static PyObject *
posix_WIFEXITED(PyObject *self, PyObject *args)
{
        WAIT_TYPE status;
        WAIT_STATUS_INT(status) = 0;

        if (!PyArg_ParseTuple(args, "i:WIFEXITED", &WAIT_STATUS_INT(status)))
                return NULL;

        return PyBool_FromLong(WIFEXITED(status));
}
#endif /* WIFEXITED */

#ifdef WEXITSTATUS
PyDoc_STRVAR(posix_WEXITSTATUS__doc__,
"WEXITSTATUS(status) -> integer\n\n\
Return the process return code from 'status'.");

static PyObject *
posix_WEXITSTATUS(PyObject *self, PyObject *args)
{
        WAIT_TYPE status;
        WAIT_STATUS_INT(status) = 0;

        if (!PyArg_ParseTuple(args, "i:WEXITSTATUS", &WAIT_STATUS_INT(status)))
                return NULL;

        return Py_BuildValue("i", WEXITSTATUS(status));
}
#endif /* WEXITSTATUS */

#ifdef WTERMSIG
PyDoc_STRVAR(posix_WTERMSIG__doc__,
"WTERMSIG(status) -> integer\n\n\
Return the signal that terminated the process that provided the 'status'\n\
value.");

static PyObject *