Hello,
Could you put some light on this:
It's executed on AIX if that matters. The man page is not very verbose. What I've figured out myself is that cut -c removes chars from string (which is stated in manpage actually ). I've found a few examples via Google. So after -c is the chars position I suppose. Also it looks like that without the trailing dash cut just prints the char at this position.
Here is what I don't understand:
1) "ref_categorie=" is 14 chars, why -c14- leaves also the '='?
2) What's the difference between -c15- and -c1-15- ? They do the same in my case, but maybe there is something that I'm missing.
Thank you very much for your help!

Three basic formats of the -c option in the cut command

-c15 will cut character position 15
-c1-15 will cut character positions 1 thru 15
-c15- will cut from character position 15 to the end

I would think that your first two examples would be giving some kind of syntax error as they are not standard or correct.

Lastly, you can specify more character positions than simply one range. See the following
-c1-5,10-11,21-
cut positions 1 through 5, 10 through 11, and from 21 to the end

It does make sense now. Thank you very much, joeyg.