IO::Lambda::Flock(3p)

NAME
IO::Lambda::Flock - lambda-style file locking

DESCRIPTION
The module provides file locking interface for the lambda style, implemented by using non-blocking, periodic polling of flock(2).

SYNOPSIS
    open LOCK, ">lock";
    lambda {
        # obtain the lock
        context \*LOCK, timeout => 10;
        flock { die "can't obtain lock" unless shift }

        # while reading from handle
        context $handle;
        readable { ... }

        # and showing status
        context 0.5;
        timeout { print '.'; again }
    };

API

flock($filehandle, %options) -> ($lock_obtained = 1 | $timeout = 0)
    Waits until the file lock is obtained or the timeout is expired. When successful, the (shared or exclusive) lock on $filehandle is acquired by "flock($filehandle, LOCK_NB)" call. Options:

    "timeout" or "deadline"
        These two options are synonyms, both declare the moment when the lambda waiting for the lock should give up. If undef, timeout never occurs.

    shared
        If set, "LOCK_SH" is used, otherwise "LOCK_EX".

    frequency
        Defines how often the polling for the lock should occur. If left undefined, polling occurs during idle time, when other events are dispatched.

SEE ALSO
Fcntl, IO::Lambda::Poll.

AUTHOR
Dmitry Karasik, <dmitry@karasik.eu.org>.