source: trunk/essentials/dev-lang/perl/lib/dotsh.pl

#
#   @(#)dotsh.pl                                               03/19/94
#
# This library is no longer being maintained, and is included for backward
# compatibility with Perl 4 programs which may require it.
#
# In particular, this should not be used as an example of modern Perl
# programming techniques.
#
#
#   Author: Charles Collins
#
#   Description:
#      This routine takes a shell script and 'dots' it into the current perl
#      environment. This makes it possible to use existing system scripts
#      to alter environment variables on the fly.
#
#   Usage:
#      &dotsh ('ShellScript', 'DependentVariable(s)');
#
#         where
#
#      'ShellScript' is the full name of the shell script to be dotted
#
#      'DependentVariable(s)' is an optional list of shell variables in the
#         form VARIABLE=VALUE,VARIABLE=VALUE,... that 'ShellScript' is
#         dependent upon. These variables MUST be defined using shell syntax.
#
#   Example:
#      &dotsh ('/foo/bar', 'arg1');
#      &dotsh ('/foo/bar');
#      &dotsh ('/foo/bar arg1 ... argN');
#
sub dotsh {
   local(@sh) = @_;
   local($tmp,$key,$shell,$command,$args,$vars) = '';
   local(*dotsh);
   undef *dotsh;
   $dotsh = shift(@sh);
   @dotsh = split (/\s/, $dotsh);
   $command = shift (@dotsh);
   $args = join (" ", @dotsh);
   $vars = join ("\n", @sh);
   open (_SH_ENV, "$command") || die "Could not open $dotsh!\n";
   chop($_ = <_SH_ENV>);
   $shell = "$1 -c" if ($_ =~ /^\#\!\s*(\S+(\/sh|\/ksh|\/zsh|\/csh))\s*$/);
   close (_SH_ENV);
   if (!$shell) {
      if ($ENV{'SHELL'} =~ /\/sh$|\/ksh$|\/zsh$|\/bash$|\/csh$/) {
         $shell = "$ENV{'SHELL'} -c";
      } else {
         print "SHELL not recognized!\nUsing /bin/sh...\n";
         $shell = "/bin/sh -c";
      }
   }