Hi oombera,
What Perderabo wrote sounds good, but really doesn't work for me, I just tried it again, the temp-directories still are in the archive. Also the way you described didn't work for me. Then the temp-directories are again in my archive.
But I've got a way that does work for me, it is not ideal, but it is working. It is the following:
tar -cvf /tmp/datadir.tar --exclude=temp1 --exclude=temp2 --exclude=temp3 /appl/data
You were also wondering why I am concerned with this. Well that is because of my daily backup of the whole system. Every day I want to make a backup on tape of the whole system, but not of the temp-directories. While the backup is being made other proces can be running changing files in the tempdirectories. Files in these directories change while in the meantime backup is trying to write them to tape, because of this the backup can crash. So that is the reason. Hope you understand me.
Anyway I am very thankful for all your help.