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From: Didier Derny <didier@omnix.fr.org>
Message-Id: <199507261104.NAA06581@zapata.omnix.fr.org>
Subject: sleep / alarm conflict
To: questions@freebsd.org
Date: Wed, 26 Jul 1995 13:04:24 +0200 (MET DST)
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this sequence:

#include <stdio.h>
#include <sys/types.h>
#include <setjmp.h>
#include <limits.h>
#include <float.h>
#include <fcntl.h>
#include <signal.h>


static jmp_buf jumpenv;

ReadLineAlarm()
{
  signal(SIGALRM, SIG_IGN);
  alarm(0);
  fprintf(stderr, "alarm signal caught\n");
  longjmp(jumpenv, 1);
}

main()
{
  signal(SIGALRM, ReadLineAlarm);
  if (setjmp(jumpenv) != 0) 
    return;
  alarm(2);
  for (;;)
    sleep(1);
}

never end.

Is it normal or a bug.


this sequence works if alarm is replaced by an infinite loop.


+---------------------+
| Didier Derny        |
| didier@omnix.fr.org |
+---------------------+