The ev 1.x EvIo has a property named fd. Its not a reference of the original fd. For example,
<?php
$fd = socket_create(...);
$w = new EvIo($fd, Ev::READ, function ($watcher, $revents) {
var_dump($watcher);
fgets($watcher->fd);
});
Ev::run();
We register the $fd into to loop. When the event occurring, we want get
the original $fd from the $watcher->fd. However, in the 1.x, the
property fd is a presudo property, and it references the real fd of the
STDIN. When you read this property you will get a new stream resource.
So you cannot use the socket_* function. And instead, you need transfer the
original fd in you own way.
I made a PR, but be declined.
ev is a PECL extension providing interface to libev library - high performance full-featured event loop written in C.
Libev is an event loop: you register interest in certain events (such as a file descriptor being readable or a timeout occurring), and it will manage these event sources and provide your program with events.
To do this, it must take more or less complete control over your process (or thread) by executing the event loop handler, and will then communicate events via a callback mechanism.
You register interest in certain events by registering so-called event watchers, and then hand it over to libev by starting the watcher.
For details refer to the libev's homepage: http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#EMBEDDING
For installation instructions see file named INSTALL.
You don't need to install libev separately, since it is embedded into this extension.
Currently GNU/Linux platforms supported only. But likely will work on others too.
<?php
// Create and start timer firing after 2 seconds
$w1 = new EvTimer(2, 0, function () {
echo "2 seconds elapsed\n";
});
// Create and launch timer firing after 2 seconds repeating each second
// until we manually stop it
$w2 = new EvTimer(2, 1, function ($w) {
echo "is called every second, is launched after 2 seconds\n";
echo "iteration = ", Ev::iteration(), PHP_EOL;
// Stop the watcher after 5 iterations
Ev::iteration() == 5 and $w->stop();
// Stop the watcher if further calls cause more than 10 iterations
Ev::iteration() >= 10 and $w->stop();
});
// Create stopped timer. It will be inactive until we start it ourselves
$w_stopped = EvTimer::createStopped(10, 5, function($w) {
echo "Callback of a timer created as stopped\n";
// Stop the watcher after 2 iterations
Ev::iteration() >= 2 and $w->stop();
});
// Loop until Ev::stop() is called or all of watchers stop
Ev::run();
// Start and look if it works
$w_stopped->start();
echo "Run single iteration\n";
Ev::run(Ev::RUN_ONCE);
echo "Restart the second watcher and try to handle the same events, but don't block\n";
$w2->again();
Ev::run(Ev::RUN_NOWAIT);
$w = new EvTimer(10, 0, function() {});
echo "Running a blocking loop\n";
Ev::run();
echo "END\n";
?>
Output
2 seconds elapsed
is called every second, is launched after 2 seconds
iteration = 1
is called every second, is launched after 2 seconds
iteration = 2
is called every second, is launched after 2 seconds
iteration = 3
is called every second, is launched after 2 seconds
iteration = 4
is called every second, is launched after 2 seconds
iteration = 5
Run single iteration
Callback of a timer created as stopped
Restart the second watcher and try to handle the same events, but don't block
Running a blocking loop
is called every second, is launched after 2 seconds
iteration = 8
is called every second, is launched after 2 seconds
iteration = 9
is called every second, is launched after 2 seconds
iteration = 10
END
Example 1
<?php
// Tick each 10.5 seconds
$w = new EvPeriodic(0., 10.5, NULL, function ($w, $revents) {
echo time(), PHP_EOL;
});
Ev::run();
?>
Example 2
<?php
// Tick each 10.5 seconds. Use reschedule callback
function reschedule_cb ($watcher, $now) {
return $now + (10.5. - fmod($now, 10.5));
}
$w = new EvPeriodic(0., 0., "reschedule_cb", function ($w, $revents) {
echo time(), PHP_EOL;
});
Ev::run();
?>
Example 3
<?php
// Tick every 10.5 seconds starting at now
$w = new EvPeriodic(fmod(Ev::now(), 10.5), 10.5, NULL, function ($w, $revents) {
echo time(), PHP_EOL;
});
Ev::run();
?>
Example 1
<?php
// Wait until STDIN is readable
$w = new EvIo(STDIN, Ev::READ, function ($watcher, $revents) {
echo "STDIN is readable\n";
});
Ev::run(Ev::RUN_ONCE);
?>
Example 2
<?php
/* Use some async I/O to access a socket */
// `sockets' extension still logs warnings
// for EINPROGRESS, EAGAIN/EWOULDBLOCK etc.
error_reporting(E_ERROR);
$e_nonblocking = array (/*EAGAIN or EWOULDBLOCK*/11, /*EINPROGRESS*/115);
// Get the port for the WWW service
$service_port = getservbyname('www', 'tcp');
// Get the IP address for the target host
$address = gethostbyname('google.co.uk');
// Create a TCP/IP socket
$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
if ($socket === FALSE) {
echo "socket_create() failed: reason: "
.socket_strerror(socket_last_error()) . "\n";
}
// Set O_NONBLOCK flag
socket_set_nonblock($socket);
// Abort on timeout
$timeout_watcher = new EvTimer(10.0, 0., function ($w) {
socket_close($w->fd);
Ev::stop(Ev::BREAK_ALL);
});
// Make HEAD request when the socket is writable
$write_watcher = new EvIo($socket, Ev::WRITE, function ($w)
use ($timeout_watcher, $e_nonblocking) {
$socket = $w->fd;
// Stop timeout watcher
$timeout_watcher->stop();
// Stop write watcher
$w->stop();
$in = "HEAD / HTTP/1.1\r\n";
$in .= "Host: google.co.uk\r\n";
$in .= "Connection: Close\r\n\r\n";
if (!socket_write($socket, $in, strlen($in))) {
trigger_error("Failed writing $in to socket", E_USER_ERROR);
}
$read_watcher = new EvIo($socket, Ev::READ, function ($w, $re)
use ($e_nonblocking) {
$socket = $w->fd;
// Socket is readable. recv() 20 bytes using non-blocking mode
$ret = socket_recv($socket, $out, 20, MSG_DONTWAIT);
if ($ret) {
echo $out;
} elseif ($ret === 0) {
// All read
$w->stop();
socket_close($socket);
return;
}
// Caught EINPROGRESS, EAGAIN, or EWOULDBLOCK
if (in_array(socket_last_error(), $e_nonblocking)) {
return;
}
$w->stop();
socket_close($socket);
});
Ev::run();
});
$result = socket_connect($socket, $address, $service_port);
Ev::run();
?>
Sample output:
HTTP/1.1 301 Moved Permanently
Location: http://www.google.co.uk/
Content-Type: text/html; charset=UTF-8
Date: Sun, 23 Dec 2012 16:08:27 GMT
Expires: Tue, 22 Jan 2012 16:08:27 GMT
Cache-Control: public, max-age=2592000
Server: gws
Content-Length: 221
X-XSS-Protection: 1; mode=block
X-Frame-Options: SAMEORIGIN
Connection: close
Example 1
<?php
/*
* Try to get an embeddable event loop and embed it into the default event loop.
* If it is impossible, use the default
* loop. The default loop is stored in `$loop_hi`, while the embeddable loop is
* stored in `$loop_lo`(which is `$loop_hi` in the case no embeddable loop can be
* used).
*
* Sample translated to PHP
* <http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#Examples_CONTENT-9>
*/
$loop_hi = EvLoop::defaultLoop();
$loop_lo = NULL;
$embed = NULL;
/*
* See if there is a chance of getting one that works
* (flags' value of 0 means autodetection)
*/
$loop_lo = Ev::embeddableBackends() & Ev::recommendedBackends()
? new EvLoop(Ev::embeddableBackends() & Ev::recommendedBackends())
: 0;
if ($loop_lo) {
$embed = new EvEmbed($loop_lo, function () {});
} else {
$loop_lo = $loop_hi;
}
?>
Example 2
<?php
/*
* Check if kqueue is available but not recommended and create a kqueue backend
* for use with sockets (which usually work with any kqueue implementation).
* Store the kqueue/socket-only event loop in `$socket_loop`. (One might optionally
* use `EVFLAG_NOENV`, too)
*
* Example borrowed from
* <http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#Examples_CONTENT-9>
*/
$loop = EvLoop::defaultLoop();
$socket_loop = NULL;
$embed = NULL;
if (Ev::supportedBackends() & ~Ev::recommendedBackends() & Ev::BACKEND_KQUEUE) {
if (($socket_loop = new EvLoop(Ev::BACKEND_KQUEUE))) {
$embed = new EvEmbed($loop);
}
}
if (!$socket_loop) {
$socket_loop = $loop;
}
// Now use $socket_loop for all sockets, and $loop for anything else
?>
<?php
// Handle SIGTERM signal
$w = new EvSignal(SIGTERM, function ($watcher) {
echo "SIGTERM received\n";
$watcher->stop();
});
Ev::run();
?>
Example 1
<?php
// Monitor changes of /var/log/messages.
// Use 10 second update interval.
$w = new EvStat("/var/log/messages", 8, function ($w) {
echo "/var/log/messages changed\n";
$attr = $w->attr();
if ($attr['nlink']) {
printf("Current size: %ld\n", $attr['size']);
printf("Current atime: %ld\n", $attr['atime']);
printf("Current mtime: %ld\n", $attr['mtime']);
} else {
fprintf(STDERR, "`messages` file is not there!");
$w->stop();
}
});
Ev::run();
?>
Example 2
<?php
// Avoid missing updates by means of one second delay
$timer = EvTimer::createStopped(0., 1.02, function ($w) {
$w->stop();
$stat = $w->data;
// 1 second after the most recent change of the file
printf("Current size: %ld\n", $stat->attr()['size']);
});
$stat = new EvStat("/var/log/messages", 0., function () use ($timer) {
// Reset timer watcher
$timer->again();
});
$timer->data = $stat;
Ev::run();
?>
<?php
$pid = pcntl_fork();
if ($pid == -1) {
fprintf(STDERR, "pcntl_fork failed\n");
} elseif ($pid) {
$w = new EvChild($pid, FALSE, function ($w, $revents) {
$w->stop();
printf("Process %d exited with status %d\n", $w->rpid, $w->rstatus);
});
Ev::run();
// Protect against Zombies
pcntl_wait($status);
} else {
//Forked child
exit(2);
}
?>
Ruslan Osmanov osmanov@php.net
Copyright (c) 2012,2013,2014 Ruslan Osmanov <osmanov@php.net>
This project is subject to version 3.01 of the PHP license, that is bundled
with this package in the file LICENSE, and is available through the
world-wide-web at the following url: http://www.php.net/license/3_01.txt If you
did not receive a copy of the PHP license and are unable to obtain it through
the world-wide-web, please send a note to license@php.net so we can mail you a
copy immediately.