Re: How to timeout a while loop?

You want a die 'timeout'; in your $SIG{ALRM} that will break you out at the end of your eval (put a ; at the end of that eval) then put your code catch code... like so

$SIG{ALRM} = sub {die 'timeout'};
while ( $number < 10 ) {

   eval {

      alarm(3);

      print $number;
   
      if ( $number == 3 ) { sleep 4; } # This is to simulate the delay
+ the routines may generate...
   
      $number++;
   
      print "\n";
   };

   alarm(0);

   if($@ eq 'timeout') {
     next;
   } else {
     die $@;
   } 

}
[download]

Not tested, but should get you pointed in the right direction. Alarm 0 is important to unset the alarm.

- Ant
- Some of my best work - (1 2 3)

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Re^2: How to timeout a while loop? by Andre_br (Pilgrim) on Apr 25, 2005 at 20:36 UTC
Hey Suaveant, Great! Thanks a lot; in fact i needed to change some details for it to work, like putting the sub that listens the $@ outside the while, but now it is just perfect. Here´s the final code, for the monk's record: `my $number = 0; $SIG{ALRM} = sub {die 'timeout'}; while ( $number < 10 ) { eval { $number++; alarm(3); if ( $number == 3 ) { sleep 4; } # This is to simulate the delay + the routines may generate... print $number; print "\n"; }; alarm(0); } if($@ eq 'timeout') { next; } else { die $@; }` [download] Thanks a lot, my friend Andre_br	[reply] [d/l]
Re^3: How to timeout a while loop? by suaveant (Parson) on Apr 25, 2005 at 20:47 UTC
Umm.. if you leave the if at the bottom outside the while the next is useless, and any $@ values will cause the loop to continue, including non-timeout values. You could possibly also miss valid die messages. To be really useful you should probably check the $@ at the end of the eval after the alarm(0); - Ant - Some of my best work - (1 2 3)	[reply]