Shells and Scripting (18)

Back-quotes (cont)

Example: convert GIF files to PNG format.

Original and converted files share the same prefix
(e.g. /x/y/abc.gif is converted to /x/y/abc.png)

#!/bin/sh
# ungif - convert gifs to PNG format

for f in $@
do
    dir=`dirname "$f"`
    prefix=`basename "$f" .gif`
    outfile="$dir/$prefix.png"
    giftopnm "$f" | pnmtopng > $outfile
done