portability for lunix

osxbackup/rsyncbackup.command

@@ -63,6 +63,7 @@ RE+=" --exclude=/Library/Containers/com.docker.docker/"
 RE+=" --exclude=/Library/Cookies/"
 RE+=" --exclude=/Library/Developer/"
 RE+=" --exclude=/Library/Homebrew/"
+RE+=" --exclude=/Library/Syncthing/folders/" # syncthing is its own backup
 RE+=" --exclude=/Library/Logs/"
 RE+=" --exclude=/Library/Mail/" # keep your mail on the server!
 RE+=" --exclude=/Library/Mail?Downloads/"
@@ -174,9 +175,11 @@ RE+=" --exclude=/iBooks.app"
 RE+=" --exclude=/iMovie.app"
 RE+=" --exclude=/iTunes.app"
 
-RETVAL=255
-while [ $RETVAL -ne 0 ]; do
-    $RSYNC $OPTS $RE $MINRE /Applications/ ${BACKUPDEST}/Applications/
-    RETVAL=$?
-    sleep 1;
-done
+if [[ "$(uname)" = "Darwin" ]]; then
+    RETVAL=255
+    while [ $RETVAL -ne 0 ]; do
+        $RSYNC $OPTS $RE $MINRE /Applications/ ${BACKUPDEST}/Applications/
+        RETVAL=$?
+        sleep 1;
+    done
+fi