From owner-freebsd-hackers  Tue Sep 15 03:22:47 1998
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Date: Tue, 15 Sep 1998 12:22:11 +0200 (CEST)
From: Konrad Heuer <kheuer@gwdu60.gwdg.de>
To: freebsd-hackers@FreeBSD.ORG
Subject: Catching SIGSEGV
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May I ask my question here although it's not correlated to FreeBSD
development?

I write a program which shall run under FreeBSD and want to catch SIGSEGV
to count these events. So the program is like this: 

int nsegv = 0;
int *ptr;
int zero = 0; 

void sighdl ( int sig )
{
  ptr = &zero;
  nsegv++; 
}

int dowork ( )
{
  int buf;

  signal(SIGSEGV, sighdl);

  ptr = InvalidAddress;
  buf = *ptr;
}

Ok, the signal handler gets called, ptr will be reset to a legal address,
but nevertheless after returning from the signal handler it will be called
again immediately resulting in an infinite loop.

Where's my mistake? What can I do to prevent that loop?
Thanks for any reply.

Regards
Konrad Heuer

// Gesellschaft fuer wissenschaftliche Datenverarbeitung mbH
// Goettingen (GWDG), Am Fassberg, D-37077 Goettingen, Germany
//
// kheuer@gwdu60.gwdg.de


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