Detect rsync and its protocol version

diff --git a/bin/backup-script b/bin/backup-script
index b38a8f33488627f19c999d9e0bc68ba80ad72e8f..670f6991fbd30c2b903e8cab55997d1967db8067 100755 (executable)
--- a/bin/backup-script
+++ b/bin/backup-script
@@ -298,12 +298,25 @@ while [ $# -gt 0 ]; do
        esac
 done
 
-trap GotSignal SIGINT
-
 echo -n "Started: "; date
 echo -e $config_info
+
+# Check rsync and its protocol version
+rsync=$(which "rsync" 2>/dev/null)
+if [ $? -ne 0 ]; then
+       echo "Failed to detect rsync(1)! Is it installed in your \$PATH?"
+       exit 1
+fi
+rsync_proto=$($rsync --version 2>/dev/null | head -n 1 | sed 's/.*  protocol version \([0-9]*\)$/\1/')
+if [ $? -ne 0 ]; then
+       echo "Failed to detect protocol version of $rsync!"
+       exit 1
+fi
+echo "Rsync command is $rsync, protocol version $rsync_proto."
 echo
 
+trap GotSignal SIGINT
+
 if [ $# -ge 1 ]; then
        for s in "$@"; do
                if [ ! -r "${conf_d}/$s" ]; then
@@ -525,7 +538,7 @@ for f in $sys; do
        fi
 
        # prepare (remote) command ...
-       cmd="rsync --archive"
+       cmd="$rsync --archive"
        [ "$compress" -ne 0 ] && cmd="$cmd --compress"
        [ "$local" -eq 0 ] && cmd="$cmd --rsh=\"$ssh_cmd\""
        cmd="$cmd --delete --delete-excluded --sparse"