Hi,

I am trying to do the following:

Step through a foreach loop and call a funtion.
The function may take a very long time to complete but I only want to wait a finite period of time and if the function has not completed, go to the next iteration of the loop.

I am using an alarm() with a call to a signal handler in order to acomplish this.

My problem is that when I try to use a goto withing the signal handler, I get the following error:

Can't find label LABEL at ./t21.pl line 18.

I should mention that I running this in a Win32 (Win 2K) machine and I am aware of all the caveats that apply to signal handling on this OS.

Aparently the alarm() call is now supported on Win32 for Active State Perl 5.8.0. which I am using(See article here) and it appears to work fine.

Here is my code: 

sub callfc()
{
        # just keep printing until the signal goes off
        for ($i = 0; $i < 1000; $i++)
        {
                print "$i \n";
                sleep(1);
        }
}
        for ($j = 0; $j < 1000000; $j++)
        {
                # set signal time out
                alarm(2);
                # set up signal handler
                $SIG{ALRM} = sub { goto "LABEL"; };
                # call the function
                &callfc();
LABEL: # hopefully skip to the next iteration of the loop
        }

print "I am continuing with the code\n";
sleep(1);
print "I am continuing with the code\n";

[download]

for the test code above, I've used a simple for loop but the same principle applies.

Does anyone have any suggestions on how to acomplish what I am trying to do, either with the (much frowned upon goto) or any other way.

Thanks for your help!

Kakaze

In reply to GOTO, Signals and Win32 by kakaze

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