- eval "app=\${$appvar-$app}"
- inst_ver=$(get_version $app)
- if [ ! "$inst_ver" ]; then
- echo "$me: Error: '$app' not found" >&2
- ret=1
- elif [ ! "$req_ver" = "-" ]; then
- latest_ver=$(sort_ver $req_ver $inst_ver | cut -d' ' -f2)
- if [ ! "$latest_ver" = "$inst_ver" ]; then
- echo "$me: Error: '$app' version == $inst_ver is too old" >&2
- echo " '$app' version >= $req_ver is required" >&2
+ case $appvar in
+ GZIP) ;; # Do not use $GZIP: it contains gzip options.
+ *) eval "app=\${$appvar-$app}" ;;
+ esac
+ if [ "$req_ver" = "-" ]; then
+ # Merely require app to exist; not all prereq apps are well-behaved
+ # so we have to rely on $? rather than get_version.
+ $app --version >/dev/null 2>&1
+ if [ 126 -le $? ]; then
+ echo "$me: Error: '$app' not found" >&2