Re: A86: Hiding Programs

To: assembly-86@lists.ticalc.org
Subject: Re: A86: Hiding Programs
From: Ben Mickle <bmickle@yahoo.com>
Date: Sat, 24 Apr 1999 05:05:26 -0700 (PDT)
Delivered-To: assembly-86-outgoing@towerguard.unix.edu.sollentuna.se
Delivered-To: assembly-86@lists.ticalc.org
Reply-To: assembly-86@lists.ticalc.org




--- JBrett <tbarwick@esn.net> wrote:
> 
> >If the first character of a program is less than
> 'A',
> >then it is not detected by any shells or the os. 
> To
> >hide a program like this, use this routine (it
> isn't
> >tested):
> >
> > ld hl,progname-1
> > rst 20h
> > rst 10h
> 
> call _FINDSYM returns the pointer to the absolute
> address in bde, not ahl...
> so first, you'd have to do:
> ex hl,de
> ld a,b
> to get the pointer into ahl...

rst 10h returns the pointer to the VAT entry in hl. 
It does matter about the actual program data.  So, you
do not need to do that.

> 
> > ld de,6
> 
> I'm not sure how many type bytes there are in a
> program variable at the
> moment... so I'm guessing this is correct...
> 
> > add hl,de    ;point hl to first character in VAT
> > ld (hl),0
> 
>    ret =)
> _________
> JBrett
> tbarwick@esn.net - http://brett.acz.org
> ICQ UIN: 20607010
> AIM: BarwickBJ
> ACZ member - http://www.acz.org
> 
> 
> 

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