Sender:	root AT delorie DOT com
Message-ID:	<386A0341.BA78509@inti.gov.ar>
Date:	Wed, 29 Dec 1999 09:49:05 -0300
From:	salvador <salvador AT inti DOT gov DOT ar>
Organization:	INTI
X-Mailer:	Mozilla 4.6 [en] (X11; I; Linux 2.0.38 i686)
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To:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
CC:	djgpp AT delorie DOT com
Subject:	Re: GDB, DOS 6.22, CWSDPMI and Interrupts
References:	<Pine DOT SUN DOT 3 DOT 91 DOT 991229102731 DOT 11728S-100000 AT is>
Reply-To:	djgpp AT delorie DOT com

Eli Zaretskii wrote:

> On Tue, 28 Dec 1999, salvador wrote:
>
> >   I have a big problem using gdb (4.16 or RHIDE with gdb 4.17 or 4.18 inside)
> > under DOS 6.22 (and CWSDPMI as DPMI host).
> >   The program I'm trying to debug runs ok if I run it outside the debugger. But
> > if I run the program inside the debugger it just freeze.
> >   After some hard research I found the reason: interrupts are disabled!
>
> I have successfully run under GDB 4.18 programs that use setitimer, so
> interrupts are not disabled in general under a debugger.

Did your program call any real mode stuff between interrupts?

>  Also, SIGINT
> uses the keyboard interrupt, so if your program gets SIGINT when run
> under a debugger, interrupts are not disabled.

No, I'm not getting SIGINT.
Perhaps you overlooked the most important detail: If *I* call a real mode service
periodically interrupts work because they seems to be enabled during the PMode->Real
Mode->PMode switch. But if my code doesn't call any real mode thing I don't get any
interrupt.
As my program uses Turbo Vision and Allegro all the keyboard and mouse input is done
in protected mode. If I switch Turbo Vision to "BIOS" mode or I add a call to
bioskey in the polling loop of DEGUI all works OK.

> What version of the library (libc.a and libdbg.a) was used to compile
> RHIDE and/or GDB?

Don't know, but I got the same results with various RHIDE versions.

>  Are the GDB sources you used up-to-date (i.e., from
> gdb418s.zip on SimTel)?

Used in RHIDE? Andris should asnwer it, but I get the same results using gdb 4.16
and gdb 4.18 from Simtel (not only RHIDE 1.4.7.x)

SET

--
Salvador Eduardo Tropea (SET). (Electronics Engineer)
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