I have been using kdar to back up critical files. It's very annoying though because it's not automatic. I want an open source program that will Create a full backup each week and differential backups every day at certain times.

Does anyone know of software like this?

How about cron ?

kdar is just a GUI interface to the command-line utility dar, which can be called non-interactively. There are many backup alternatives, but if you're already using dar archives, that's one reason to carry on.

You could easily automate production of dar archives, although it would men finding out how to call it from the command-line, and putting that command (with perhaps a little extra stuff) into a script, and calling it from cron, or similar.

In fact, kdar is able to generate the dar command for you, from this dialog (the "export dar command button).

If you don't want to muck about with dar archives any more, there are plenty of other solutions. I rather like dar archives. They add quite a lot of nice functionality missing from tarballs.

I don't have a problem with the command line if it is able to automatically use the last full or differential backup to create a differential or incremental backup. But so far, I can't see any way to do that (easily).

Describe more how you are using kdar. You make one full backup how often, and how often a differential? Do you make the backup onto a permanently mounted drive, a manually mounted external drive, a network drive, or burn to CDs/DVDs?

I want to use it to make backups of my C++ source code every day. On the same hard drive but in a different dir. Which I tested today. Every time I want to make a backup, I need to go through all of the steps manually.

I can create a script that will do full backups every day using dar but using a script to find the last full backup to make a differential is tough.

There are loads of backup scripts around the net. For sure you can find one which matches your requirements. I googed and found this one which looks quite nice:

http://www.methods.co.nz/yakup/

Thanks. I was able to use that code to fix a problem I was having appending function output in strings. I am going to name the backups with the date and time.

#t=$(date '+%F_%T');
#path="/home/Storage/Backups/cpp_$t _diff"; #won't work without space after $t
path="/home/Storage/Backups/cpp_$(date '+%F_%T')_diff"; #best choice for now
echo $path