tools/batch_* scripts: verify number of arguments before invoking 'shift'.

tools/batch_crop.in

@@ -12,14 +12,9 @@
 VIPSHOME=${VIPSHOME-@prefix@}
 
 name=`basename $0`
-left=$1
-top=$2
-width=$3
-height=$4
-shift 4
 
 # check args
-if [ $# -lt 1 ]; then
+if [ $# -lt 5 ]; then
 	echo "usage: $name left top width height image1 image2 ..."
 	echo 
 	echo "$name writes a new set of images called crop_image1, "
@@ -28,6 +23,12 @@ if [ $# -lt 1 ]; then
 	exit 1
 fi
 
+left=$1
+top=$2
+width=$3
+height=$4
+shift 4
+
 # convert each argument
 for i in $*; do
 	dir=`dirname $i`

tools/batch_image_convert.in

@@ -12,11 +12,9 @@
 VIPSHOME=${VIPSHOME-@prefix@}
 
 name=`basename $0`
-type=$1
-shift
 
 # check args
-if [ $# -lt 1 ]; then
+if [ $# -lt 2 ]; then
 	echo "usage: $name <new image type> image1 image2 ..."
 	echo 
 	echo "$name uses VIPS to convert a group of image files of"
@@ -27,6 +25,9 @@ if [ $# -lt 1 ]; then
 	exit 1
 fi
 
+type=$1
+shift
+
 # convert each argument
 for i in $*; do
 	# drop the suffix on the filename

tools/batch_rubber_sheet.in

@@ -14,11 +14,9 @@ VIPSHOME=${VIPSHOME-@prefix@}
 
 # get name we were run as
 name=`basename $0`
-rec=$1
-shift
 
 # check args
-if [ $# -lt 1 ]; then
+if [ $# -lt 2 ]; then
 	echo "usage: $name matrix image1 image2 ..."
 	echo "writes rsc_image1, rsc_image2, ..."
 	echo
@@ -28,6 +26,9 @@ if [ $# -lt 1 ]; then
         exit 1
 fi
 
+rec=$1
+shift
+
 # transform each argument
 for i in $*; do
 	echo "Transforming $i to rsc_$i ..."