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remote-backup

@@ -6,20 +6,59 @@
 # rotating backup-snapshots of /home whenever called
 # ----------------------------------------------------------------------
 
-unset PATH	# suggestion from H. Milz: avoid accidental use of $PATH
+#unset PATH	# suggestion from H. Milz: avoid accidental use of $PATH
 
 # ------------- system commands used by this script --------------------
-ID=/usr/bin/id;
-ECHO=/bin/echo;
 
-MOUNT=/bin/mount;
+###BEGIN: generic tool checker
-RM=/bin/rm;
+# FIXME: To reuse this function, be sure to edit this line (space separated
-MV=/bin/mv;
+# list).
-CP=/bin/cp;
+needed_tools="id echo mount rm mv cp touch rsync"
-TOUCH=/bin/touch;
+#
+# One shall not need edit anything below this line
+###
+checktools() {
+	# This functions attempts to be generic enough to be reused in any program
+	# that needs to check that specific tools are present on the system
+	# and can be found in the PATH 
+	var=$(echo $1 | tr '[:lower:]' '[:upper:]')
+	echo -n "# Looking for $1... "
+	local_var="$(which $1)"
+	eval $var="$local_var"
+	if [ -z "$local_var" ]
+	then
+		echo 'NOT FOUND!'
+		NOTFOUND="$NOTFOUND$1 "
+		DIE=1
+	else
+		echo "$local_var"
+		FOUND="$FOUND$1 "
+	fi
+	unset local_var
+}
 
-RSYNC=/usr/bin/rsync;
+for tool in $needed_tools
+do
+	checktools "$tool"
+done
 
+echo
+echo "# Found $FOUND"
+echo
+
+if [ -n "$DIE" ]
+then
+	echo "Some tools were not found, please check your installation" >&2
+	echo "Needed tools: $needed_tools" >&2
+	echo -n "Not found:" >&2
+	for tool in $NOTFOUND
+	do
+		echo -n " $tool" >&2
+	done
+	echo '!' >&2
+	exit 127
+fi
+###END: generic tool checker
 
 # ------------- file locations -----------------------------------------