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From: Bobster@cup.portal.com (Robert Jules Shaughnessy)
Newsgroups: comp.sys.atari.st.tech
Subject: Re: Can my program find its name?
Message-ID: <39432@cup.portal.com>
Date: 20 Feb 91 00:55:57 GMT
References: <2133022@nuthaus.UUCP>
Organization: The Portal System (TM)
Lines: 29


     Just a thought, but you might be interested in my train of thought.
 
A file is executed by the following:

pea    env     Enviroment
pea    com     Comand Line Address
pea    fil     file name address (What you want)
move.w #0,-(sp) Load and Start (Execute the file)
move.w #$4b,-(sp) Function number
trap   #1      (Call gemdos)
add.l  #16,sp  correct the stack
 With this in mind, all you should have to do is the followin
    
sub #4,sp  (Subtract 4 from the stack pointer and you should be pointing
            at the address of the file name. (This could be -8 instead of 4))
movea (sp)+,a0  (Move the file name address into a0)
Now all you need to do is start reading at that address until you hit a 
0 (End of file name marker) and you will have the file name the original
program used. (I think this will work in all situations. Be sure to not
mess with the stack before you do this though. It will probably need to be
the first thing you do. Oh and dont forget to correct the stack when you
done.) 

I am not 100% I have this correct, but I am sure someone will tell me if I am 
at error... ;^)


I hope this helps a little.