Hi all

I have written a simple multithread perl script which has to stopped when it receives a INT signal.

Most of the time, the execution terminated with a "perl: double free or corruption".

Anyone can help me to fix it?

Thanks

Yann

#!/bin/env perl

use Getopt::Std;
use threads;
use threads::shared;
use Time::HiRes qw( usleep );

use POSIX ();
# POSIX unmasks the sigprocmask properly
my $sigset = POSIX::SigSet->new();
my $action = POSIX::SigAction->new('stopInt',
                                 $sigset,
                                 &POSIX::SA_NODEFER);

POSIX::sigaction(&POSIX::SIGINT, $action);

my %options;
&getopts("t:c:h",\%options) || &say_usage;
&say_usage if (!defined($options{c}));

my $threadNb = 5;
my $cmd = $options{c};
my $count : shared = 0;
my $run : shared = 1;

$DB::single=1;

for ($i = 0; $i<$threadNb; $i++)
    {
    $threads[$i] = threads->new(\&workToDo, $cmd);
    }
for ($i = 0; $i<$threadNb; $i++)
   {
   $threads[$i]->join();
   }

print "nb exec command $cmd = $count\n";
    
sub workToDo()
   {
    my $cmd = shift;
    my $sem = shift;
    while (&getRun())
        {
        usleep(1000);
        #my $pid = open(PTCMD, "$cmd 2>&1 |");
            {
            lock($count);
            ++$count;
            }
        }
    print "end workToDo\n";
    }
    
sub getRun
    {
    lock($run);
    return $run;    
    }

sub stopInt
    {
    print "stopInt \n";
    lock($run);
    if ($run)
        {
        print "stop received\n";
        $run = 0;
        }
    }
    
sub say_usage 
   {
   
   print "command MT - outil de lancement d'une commande shell en Mult
+i thread\n";
   print "\n\t$0  ...\n";
   print << 'EOT';
   
   Options:
   -c    :              shell command
   [-t]  :              thread number (default: nb Thread = 5)
   [-h]  :              help : show the help
   
EOT
   exit;
   }

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In reply to double free in a multithread script when signal is received by yann22

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