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epoll cpan:CTILMES last updated on 2018-09-19

epoll-0.2/

NAME

epoll - I/O event notification facility

SYNOPSIS

use epoll;

my $epoll = epoll.new(maxevents => 1); # 1 is default

$epoll.add($file-descriptor, :in, :out, :priority, :edge-triggered);

# timeout in milliseconds, default -1 = block forever
for $epoll.wait(:2000timeout)
{
    say "{.fd} is ready for reading" if .in;
    say "{.fd} is ready for writing" if .out;
}

# Or use chained calls:

for epoll.new.add(0, :in).wait
{
    say "ready to read on {.fd}" if .in;
}

DESCRIPTION

Simple low level interface around the Linux epoll(7) I/O event notification facility. It can monitor multiple file descriptors to see if I/O is possible on any of them. Mainly useful for interfacing with other NativeCall modules, since Perl itself has a rich I/O system. If you really want to use this with Perl IO::Handles, you can use native-descriptor() to get a suitable descriptor.

class epoll

Create a new epoll object. Maxevents is the maximum number of events that can be returned from a single call to wait.

:in EPOLLIN ready for read
:out EPOLLOUT ready for write
:priority EPOLLPRI urgent data available for read
:edge-triggered EPOLLET Edge Triggered
:one-shot EPOLLONESHOT Disables after 1 event
:mod EPOLL_CTL_MOD Modify an existing file descriptor

:mod is equivalent to EPOLL_CTL_MOD to change the events for a file descriptor already added. It will also re-enable a file descriptor disabled by :one-shot mode.

For convenience, always returns the object itself, so you can chain calls.

Remove a file descriptor previously added.

Wait for 1 or more events to occur on the add()ed file descriptors. You can specify an optional timeout in milliseconds.

Returns a List of up up to $maxevents epoll-events.

class epoll-event

The file descriptor for the event.

A bitmask of the events that occurred. You can check them like this:

if $event.events +& EPOLLIN {...}

or use the much easier:

Ready to read

Ready to write

EXCEPTIONS

Throws Ad-hoc exceptions for any errors.

(Should save errno, and make real Exceptions -- patches welcome!)

NOTE

epoll is a Linux specific mechanism, and is typically not available on other architectures.

LICENSE

Copyright © 2017 United States Government as represented by the Administrator of the National Aeronautics and Space Administration. No copyright is claimed in the United States under Title 17, U.S.Code. All Other Rights Reserved.