source: vendor/bash/3.1/examples/scripts.v2/fman

#! /bin/bash
#
# original from:
# fman: new man program
# @(#) fman.ksh 1.5 94/04/16
# 91/07/03 john h. dubois iii ([email protected])
# 91/07/11 made it unpack man pages if neccessary
# 91/07/16 fixed test for whether man file pattern was expanded
# 92/01/21 made it read /etc/default/man to get section order,
#          and only display the first section found.
# 92/02/06 changed name to fman
# 92/02/07 fixed bug in notfound
# 92/02/13 incorporated changes from DOS version
# 92/03/11 changed to use MANPATH from environment if set,
#          and search all directories given in MANPATH
# 92/03/15 exec pager or man w/o forking
# 92/05/31 try using index if one exists
# 92/10/01 Added "See also <other sections>"
# 92/10/18 If PAGER is less, search for name of man page to make it easier
#          to find information in man pages for multiple items
# 92/11/11 Make it work for compressed files not listed in index;
#          deal with man pages listed in index that don't exist.
# 93/03/30 Fixed bug in MANPATH processing
# 93/06/17 Include paths in "See also:" message if they would be needed
#          to get to a man page.  Allow MANPATH spec on command line.
# 93/07/09 Added -h and -e options.
# 94/04/16 Added x option.
#
# conversion to bash v2 syntax done by Chet Ramey

istrue()
{
        test 0 -ne "$1"
}

isfalse()
{
        test 0 -eq "$1"
}

# Finds all sections that man page $1 is in and puts them in the the
# global array Sections[].  
# The filename of each page is put in FileNames[] with the same index.
# Global vars used:
# patharr[] MANPATH directories.

FindSectionsInIndex ()
{
    typeset index indexes section mpath page=$1
    typeset -i i=0 NIndex=0

    for mpath in "${patharr[@]}"; do
        if [ -r $mpath/index ]; then
            indexes="$indexes $mpath/index"
            let NIndex+=1
        fi
    done
    [ -z "$indexes" ] && return
    # Make grep give filename
    [ NIndex -lt 2 ] && indexes="$indexes /dev/null"
    # set positional parameters to
    # indexfile:searchname pagename section ...
    # e.g.
    # /usr/man/index:FP_OFF Routines DOS
    set -- `grep "^$page[       ]" $indexes`
    while [ $# -gt 2 ]; do
        FileNames[i]=${1%%index*}cat$3/$2.$3
        Sections[i]=$3
        shift 3
        let i+=1
    done
}

# Finds all sections that man page $1 is in by searching each man directory
# in the order given in patharr[],
# and puts them in the the global array Sections[].  
# The filename of each page is put in FileNames[] with the same index.
# Global vars used:
# patharr[] MANPATH directories.