How to auto-rotate digital photos to their proper orientation/exifautotran code

This code is from Gentoo Linux's patch to jpeg lib, an improved version of http://sylvana.net/jpegcrop/exifautotran.txt

See Also: man exifautotran for i do case $i in    -v|--version) echo "exifautotran"; exit 0;;    -h|--help) cat <<EOF exifautotran [list of files]
 * 1) !/bin/sh
 * 2) exifautotran [list of files]
 * 3) Transforms JPEG files so that Exif Orientation becomes 1
 * 1) Transforms JPEG files so that Exif Orientation becomes 1

Transforms JPEG files so that Exif Orientation becomes 1 EOF exit 0;; esac

case `jpegexiforient -n "$i"` in   1) transform="";;    2) transform="-flip horizontal";; 3) transform="-rotate 180";;   4) transform="-flip vertical";; 5) transform="-transpose";;   6) transform="-rotate 90";; 7) transform="-transverse";;   8) transform="-rotate 270";; *) transform="";; esac

if test -n "$transform"; then echo Executing: jpegtran -copy all $transform $i >&2 jpegtran -copy all $transform "$i" > tempfile if test $? -ne 0; then echo Error while transforming $i - skipped. >&2   else rm "$i" mv tempfile "$i" jpegexiforient -1 "$i" > /dev/null fi fi done