make it a little bit foolprof

do_indent

@@ -1,4 +1,14 @@
 #!/bin/sh
+INDENT=`which indent`
+SED=`which sed`
+if test "$INDENT" = "" ; then
+	echo programm indent missing
+        exit
+fi
+if test "$SED" = "" ; then
+	echo programm sed missing
+        exit
+fi
 BACKUP=false
 CHECK=false
 case "$1" in
@@ -20,8 +30,8 @@ formatiere() {
 		OUT=$1
 	fi
 	cp $1 $1\~
-	cat $1\~ | indent -kr -i8 -cli8 -psl -lp | \
-	sed -e 's/^        /	/g' \
+	cat $1\~ | $INDENT -kr -i8 -cli8 -psl -lp | \
+	$SED -e 's/^        /	/g' \
     	-e 's/^\(	\+\)        /\1	/g' \
     	-e 's/^\(	\+\)        /\1	/g' \
     	-e 's/^\(	\+\)        /\1	/g' \