#!/bin/sh
#
# rdjpgcom_wrapper
#
# AUTHOR:
#   Dan Harkless                                                    <opensource@
#   http://harkless.org/dan/software/                              harkless.org>
#
# COPYRIGHT:
#   This file is Copyright (C) 2006 by Dan Harkless, and is released under the
#   GNU General Public License <http://www.gnu.org/copyleft/gpl.html>.
#
# USAGE:
#   % rdjpgcom_wrapper file1.jpg [file2.jpg...]
# 
# DESCRIPTION:
#   A wrapper around rdjpgcom that allows the specification of multiple files on
#   the commandline and that prints each comment with a prefix of 
#   "<filename>: ".  If a file has no comment, "No JPEG comment" is printed (a 
#   la rdjpgcom's existing "Not a JPEG file" error).  This can be handy for 
#   sweeping through a collection of files that are supposed to have comments to
#   find the ones that don't.
#
#   If I get a chance in the future I'll make a patch to rdjpcom and send it in
#   to the libjpeg maintainers so this wrapper won't be necessary.
#
# DATE        MODIFICATION
# ==========  ==================================================================
# 2006-08-29  Original.

for f in "$@"; do
    printf "$f: "  # a little slower than using echo -n / -e, but more portable
    comment=`rdjpgcom "$f"`
    if [ "X$comment" = "X" ]; then
        echo "No JPEG comment"
    else
        echo "$comment"
    fi
done