Xref: utzoo comp.lang.c:27021 comp.unix.questions:20667
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From: pcb@gator.cacs.usl.edu (Peter C. Bahrs)
Newsgroups: comp.lang.c,comp.unix.questions
Subject: SIGFPE signal problem
Message-ID: <5450@rouge.usl.edu>
Date: 18 Mar 90 07:52:21 GMT
Sender: anon@rouge.usl.edu
Followup-To: comp.lang.c
Distribution: usa
Organization: The Center for Advanced Computer Studies, USL
Lines: 42

I am trying to detect overflow, 0 divide and, although it may seem
unlikely, underflow.  Doesn't SIGFPE detect this?  If so, why doesn't
the following SMALL code work? 

Why and how in the heck can vendors not provide for underflow detection?
I am working on SUN 3,4 and Val 11780.

#include <stdio.h>
#include <signal.h>
#include <errno.h>

void h();
main()
{
int i=1;
float a=2.3;

signal(SIGFPE,h);
printf ("errno %d\n",errno);
i = i / 0;
a = a / 0.0;
a = 999999999999999999999999999999999999999999999999999999999999999999999999999999999.9;
printf ("%d %f\n",i,a);
}

void h()
{
printf ("testing...1 hour\n");
exit(1);
}

output:
1 inf


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| Peter C. Bahrs                                                         |
| Center For Advanced Computer Studies      INET: pcb@gator.cacs.usl.edu |
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