/usr/bin/pnmtopgm is in ivtools-bin 1.2.11a1-11.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 | #!/bin/sh
#
# pnmtopgm - derived from anytopnm
#
# Copyright 1998 Vectaport Inc.
# Copyright (C) 1991 by Jef Poskanzer.
#
# Permission to use, copy, modify, and distribute this software and its
# documentation for any purpose and without fee is hereby granted, provided
# that the above copyright notice appear in all copies and that both that
# copyright notice and this permission notice appear in supporting
# documentation. This software is provided "as is" without express or
# implied warranty.
if [ ! $# = 1 ] ; then
echo "usage: $0 <file>" 1>&2
exit 64
fi
origfile="$1"
file="$origfile"
tmpfiles=""
filetype=$(file "$file")
case "$filetype" in
*PBM* )
pnmdepth 255 "$file"
exit 0
;;
*PGM* )
cat "$file"
exit 0
;;
*PPM* )
ppmtopgm "$file"
exit 0
;;
esac
exit 65
|