Thread: parameters algorythm

I was wondering if anyone knew of an algorythm that works for command line arguments. Like in Linux you could have a program that is like

Code:

ls -l -s -R

or

Code:

ls -lsR

They can be combined or in any order. I always wondeered what the algorythm was I can't seem to write a small one myselft. When I right it, the program becomes huge just for the algorythm. This isn't homework just thought about righting a linux program. Plus I am not even out of High school so they don't even teach it. Thanx in advance