Message-Id: <m0vdaS8-000S1fC@natacha.inti.edu.ar>
Comments: Authenticated sender is <salvador AT natacha DOT inti DOT edu DOT ar>
From: "Salvador Eduardo Tropea (SET)" <salvador AT natacha DOT inti DOT edu DOT ar>
Organization: INTI
To: hotpulp AT netidea DOT com, djgpp AT delorie DOT com
Date: Fri, 27 Dec 1996 14:36:30 +0000
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Subject: Re: segment registers

Hi Shawn Betts:

> When I do an asm statement, does djgpp care if I change ES, FS, or GS?
> can I mutilate them all I want without the worry that djgpp will crash?
  ES is very used in all the libc routines that uses the CPU-string 
opcodes, so if you destroy ES you'll get a disaster.
  FS and GS can be mutilated but be aware because the libc can 
mutilate the resgisters too.

> 
> also, does DS ALWAYS hold the data selector for all my variables I ever
> declare in a program? Or does it just hold the global variable selector?
  You are in a flat memory model DS=CS=ES(=SS? I guess), so DS is 
used to access to all of your C global variables and SS to all your 
locals because you'll use EBP as base for the locals.

SET 
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Salvador Eduardo Tropea (SET).
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