Hi,

Is there documentation somewhere that would explain what needs to be done to make (eg) Math::GMP threadsafe ?

My (implicit) assertion that Math::GMP is not threadsafe is based on the fact that the following script segfaults when run on a threaded build of perl (and where Math::GMP itself has been built against a libgmp that is reentrant and threadsafe): 
use threads;
use warnings;
use Math::GMP;

$th1 = threads->new(\&start_thread1, '123' x 11);

$ret1 = $th1->join();

if(ref($ret1) eq 'Math::GMP') {
  print "\$ret1 => ", ref($ret1), " ", Math::GMP::get_str_gmp($ret1, 1
+0), "\n";
}


sub start_thread1 {
    my $mbi = Math::GMP->new($_[0]);
    return $mbi;
}

[download]
I'm seeking information that doesn't pre-suppose that the reader is threads-savvy. Just a simple "how to" (if such exists) would be best .... anything more detailed would quite likely be lost on me :-)

I have another question: Is Math::BigInt threadsafe ? On the basis that the following script outputs the expected value, I'm thinking the answer could well be "yes": 
use threads;
use warnings;
#use Math::Pari;
use Math::BigInt;

$th1 = threads->new(\&start_thread1, '123' x 11);

$ret1 = $th1->join();

print $ret1, "\n";


sub start_thread1 {
    my $mbi = Math::BigInt->new($_[0]);
    return $mbi;
}
__END__
Outputs:
123123123123123123123123123123123

[download]
But then - if I so much as load Math::Pari then that script, too, segfaults. Does that indicate that Math::BigInt is *not* threadsafe ? Or does it merely indicate that one ought not to load Math::Pari in a script that invloves threading ?

Cheers,
Rob

In reply to Writing threadsafe perl extensions by syphilis

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