Hello Monks,

I am back again with another "funny" behaviour of ActivePerl. I am using v5.12.2 on Windows 2008 SP1.

I want to read from a long-running co-process, and I want to be able to interrupt that procedure. In the meantime I want to calculate something asyncronously in a thread, but this thread should not be interruptible to join it in the end.

This code crashes my Perl interpreter: 

#! /usr/bin/perl -w

use strict;
use threads;

# Starting a co-process to read from.
my $procid = open(READ, '-|', 'perl -e "$|=1; $SIG{INT} = \'IGNORE\'; 
+for ($i=0;$i<10;$i++) {print \"Line $i\n\"; sleep 1;}"');

my $break = 0;
$SIG{INT} = sub { $break=1; };

sub calculation { local $SIG{INT} = 'IGNORE'; print("calculating somet
+hing\n"); 5; }
my $thread = async(\&calculation);

# Reading from co-process.
until ($break) {
    my $line = <READ>;
    last unless defined $line;
    print $line;
}

if ($break) { kill('ABRT', $procid); }
close(READ);

print $thread->join() ."\n";

[download]

Earlier you gave me the advice, not to use signals on Windows heavily, because they cannot be expected to work in all situations.

However, I think it is unbelievable that correct code can crash the interpreter. And, btw, the code is working properly whithout the thread. Can anybody explain?

----------

Thanks for your helping answers. I think BrowserUk gave the correct hint.

In reply to Correct code crashes ActivePerl Interpreter by heiermann

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