Hi all, I've got a bit of trouble with perl threads. What I'm trying to do is to share a Thread::Semaphore object among multiple threads ( actually I would like to embed a Thread::Semaphore within an object ). The straigthforwad approach does not work :

#!/home/philou/install/perl-5.8.2-threads/bin/perl -w

use strict;
use threads;
use threads::shared;
use Thread::Semaphore;

my $s = 'Thread::Semaphore'->new( 1 );

sub t {
  while( $s->down() ) {
    print "DOWN!\n";  
    sleep( 1 );
  }
}

'threads'->new( \&t );

while( <> ) {
  $s->up();
  print "UP!\n";
}
[download]

That is, each time I press the `Enter' key, I would expect a "DOWN!" to show up on my terminal ( if the semaphore was shared ), but nothing happens.

Declaring the `$s' variable as `shared' does not help at all :

#!/home/philou/install/perl-5.8.2-threads/bin/perl -w

use strict;
use threads;
use threads::shared;
use Thread::Semaphore;

my $s : shared = 'Thread::Semaphore'->new( 1 );

sub t {
  while( $s->down() ) {
    print "DOWN!\n";  
    sleep( 1 );
  }
}

'threads'->new( \&t );

while( <> ) {
  $s->up();
  print "UP!\n";
}
[download]

When excuting the previous piece of code, it seems that the sharedness of `$s' prevents it from being a blessed object, and I end up with :

thread failed to start: Can't call method "down" on unblessed referenc
+e at ./t.pl line 11.
[download]

So my question is: How do you share Thread::Semaphore among perl threads ?

Any suggestion appreciated.

Philou

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