inotify_init

(PECL inotify >= 0.1.2)

inotify_initInitialize an inotify instance

Beschreibung

inotify_init(): resource|false

Initialize an inotify instance for use with inotify_add_watch()

Parameter-Liste

Diese Funktion besitzt keine Parameter.

Rückgabewerte

A stream resource or false on error.

Beispiele

Beispiel #1 Example usage of inotify

<?php
// Open an inotify instance
$fd = inotify_init();

// Watch __FILE__ for metadata changes (e.g. mtime)
$watch_descriptor = inotify_add_watch($fd, __FILE__, IN_ATTRIB);

// generate an event
touch(__FILE__);

// Read events
$events = inotify_read($fd);
print_r($events);

// The following methods allows to use inotify functions without blocking on inotify_read():

// - Using stream_select() on $fd:
$read = array($fd);
$write = null;
$except = null;
stream_select($read,$write,$except,0);

// - Using stream_set_blocking() on $fd
stream_set_blocking($fd, 0);
inotify_read($fd); // Does no block, and return false if no events are pending

// - Using inotify_queue_len() to check if event queue is not empty
$queue_len = inotify_queue_len($fd); // If > 0, inotify_read() will not block

// Stop watching __FILE__ for metadata changes
inotify_rm_watch($fd, $watch_descriptor);

// Close the inotify instance
// This may have closed all watches if this was not already done
fclose($fd);

?>

Das oben gezeigte Beispiel erzeugt eine ähnliche Ausgabe wie:

array(
  array(
    'wd' => 1,     // Equals $watch_descriptor
    'mask' => 4,   // IN_ATTRIB bit is set
    'cookie' => 0, // unique id to connect related events (e.g. 
                   // IN_MOVE_FROM and IN_MOVE_TO events)
    'name' => '',  // the name of a file (e.g. if we monitored changes
                   // in a directory)
  ),
);

Siehe auch

add a note

User Contributed Notes 1 note

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11
david dot schueler at tel-billig dot de
14 years ago
Example for tailing a file (like tail -f) using inotify.<?php/** * Tail a file (UNIX only!) * Watch a file for changes using inotify and return the changed data * * @param string $file - filename of the file to be watched * @param integer $pos - actual position in the file * @return string */function tail($file,&$pos) {    // get the size of the file    if(!$pos) $pos = filesize($file);    // Open an inotify instance    $fd = inotify_init();    // Watch $file for changes.    $watch_descriptor = inotify_add_watch($fd, $file, IN_ALL_EVENTS);    // Loop forever (breaks are below)    while (true) {        // Read events (inotify_read is blocking!)        $events = inotify_read($fd);        // Loop though the events which occured        foreach ($events as $event=>$evdetails) {            // React on the event type            switch (true) {                // File was modified                case ($evdetails['mask'] & IN_MODIFY):                    // Stop watching $file for changes                    inotify_rm_watch($fd, $watch_descriptor);                    // Close the inotify instance                    fclose($fd);                    // open the file                    $fp = fopen($file,'r');                    if (!$fp) return false;                    // seek to the last EOF position                    fseek($fp,$pos);                    // read until EOF                    while (!feof($fp)) {                        $buf .= fread($fp,8192);                    }                    // save the new EOF to $pos                    $pos = ftell($fp); // (remember: $pos is called by reference)                    // close the file pointer                    fclose($fp);                    // return the new data and leave the function                    return $buf;                    // be a nice guy and program good code ;-)                    break;                    // File was moved or deleted                case ($evdetails['mask'] & IN_MOVE):                case ($evdetails['mask'] & IN_MOVE_SELF):                case ($evdetails['mask'] & IN_DELETE):                case ($evdetails['mask'] & IN_DELETE_SELF):                    // Stop watching $file for changes                    inotify_rm_watch($fd, $watch_descriptor);                    // Close the inotify instance                    fclose($fd);                    // Return a failure                    return false;                    break;            }        }    }}// Use it like that:$lastpos = 0;while (true) {    echo tail($file,$lastpos);}?>
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