Dev-Util

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docs/Sem.md  view on Meta::CPAN

Dev::Util::Sem -  Module to do Semaphore locking

# VERSION

Version v2.19.35

# SYNOPSIS

To ensure that only one instance of a program runs at a time, 
create a semaphore lock file. A second instance will wait until
the first lock is unlocked before it can proceed or it times out.

    use Dev::Util::Sem;

    my $sem = Sem->new('mylock.sem');
    ...
    $sem->unlock;

# EXPORT

    new

examples/semaphore_test.pl  view on Meta::CPAN

say "go to sleep - 5 sec";

sleep 5;

say "wake up";

say "unlocking";

$sem->unlock;

say "unlocked";

say "end";

lib/Dev/Util/Sem.pm  view on Meta::CPAN

Dev::Util::Sem -  Module to do Semaphore locking

=head1 VERSION

Version v2.19.35

=head1 SYNOPSIS

To ensure that only one instance of a program runs at a time, 
create a semaphore lock file. A second instance will wait until
the first lock is unlocked before it can proceed or it times out.

    use Dev::Util::Sem;

    my $sem = Sem->new('mylock.sem');
    ...
    $sem->unlock;

=head1 EXPORT

    new

t/07-sem.t  view on Meta::CPAN

is( file_size_equals( $expected_dir . $lock_filename, 35 ),
    1, "Lockfile should be 35 characters" );

like(
       dies {
           my $semB = Dev::Util::Sem->new( $lock_filename, 1 );
           $semB->{ fh }->autoflush();
           $semB->{ fh }->print("to come to the aid of their country!");
       },
       qr{Timeout aquiring the lock},
       "Fails when lock file is locked"
    );

$semA->unlock;

is( file_exists( $expected_dir . $lock_filename ),
    0, "Lockfile in default dir should be gone now via unlock" );

done_testing;