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Mail Archives: djgpp-workers/1999/10/14/13:33:58

Date: Thu, 14 Oct 1999 19:02:37 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
X-Sender: eliz AT is
To: Esa A E Peuha <peuha AT cc DOT helsinki DOT fi>
cc: djgpp-workers AT delorie DOT com
Subject: Re: Debugging programs with SIGALRM
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On Thu, 14 Oct 1999, Esa A E Peuha wrote:

> > Is it possible that this is because longjmp doesn't disable interrupts
> > when it fiddles with SS:ESP?  Should we CLI there?
> 
> CLI would hardly be of any use, because the processor already disables 
> interrupts (and some exceptions) between a load to SS and the following 
> instruction (a load to ESP in this case).

Right.  I forgot about that.

> However, longjmp doesn't clear
> the NT flag before issuing IRET, which will cause interesting results if
> NT happens to be set for some reason.

Why should the Nested Task flag be set?  AFAIK, the debugger and the 
debuggee are treated by the DPMI host as a single task, no?

But I will try to look at the NT flag, thanks.

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