Date:	Thu, 6 Jun 2002 08:28:21 +0300 (IDT)
From:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
X-Sender:	eliz AT is
To:	Alex Oleynikov <alex AT compuweigh DOT com>
cc:	djgpp AT delorie DOT com
Subject:	Re: Exception handling
In-Reply-To:	<ExyL8.5132$ks5.512077@news2.east.cox.net>
Message-ID:	<Pine.SUN.3.91.1020606082218.15110H@is>
MIME-Version:	1.0
Reply-To:	djgpp AT delorie DOT com
Errors-To:	nobody AT delorie DOT com
X-Mailing-List:	djgpp AT delorie DOT com
X-Unsubscribes-To:	listserv AT delorie DOT com

On Thu, 6 Jun 2002, Alex Oleynikov wrote:

> 1.First of all, I am using 'REDIR -e crash.dmp myprog.exe' to capture the
> stderr output from my application. In 99% of crash situations the resulting
> crash.dmp file is empty, although if I run the program directly I can see
> the stack traceback output on the screen. Also, if I redirect it to a
> printer it prints the whole thing fine. Why doesn't REDIR save this
> information to my file?

It does for me.  I think this is something specific to your system or 
your crashes.  What OS is that?  Can you post a short program that 
crashes, for which `redir' doesn't produce a traceback in a file?

Btw, if it's NT or Windows 2000, there's an incompatible program called 
redir.exe, so perhaps you inadvertently use that instead of the DJGPP 
version of `redir'.

> 2.I hooked my handlers to several signals (SIGINT, SIGABRT, SIGSEGV and
> SIGFPE). The handler basically saves a timestamp and the signal description
> to a file, displays a message on the screen and calls
> __djgpp_traceback_exit( ) procedure. For some reason, when SIGABRT signal is
> being processed, the computer locks up completely when calling
> __djgpp_traceback_exit(). I also tried using exit() or simply return from
> the signal handler (since the SIGABRT is raised from assert()) - the result
> is always the same - the computer locks up. Why is that?

SIGABRT is not a real exception, so it's treated a bit differently.  
However, it shouldn't lock up.  Please show the code of your signal 
handler, and how you install it, there's probably something wrong with 
that.

> 2.If I will not be able to solve the problem with REDIR, is there a way to
> get an output similar to the one produced by __djgpp_traceback_exit(), but
> without terminating the application? In other words, can I somehow save the
> stack traceback to a log file from within my signal handler?

The sources of the library are freely available: download djlsr203.zip 
and look at the file src/libc/go32/dpmiexcp.c, where you will find the 
code that prints the traceback.

- Raw text -