eio_grp

Creates a request group

Description

resource eio_grp(callable $callback, string $data = NULL)

eio_grp creates a request group.

Parameters

callback

callback function is called when the request is done. It should match the following prototype:

void callback(mixed $data, int $result[, resource $req]);
data

is custom data passed to the request.

result

request-specific result value; basically, the value returned by corresponding system call.

req

is optional request resource which can be used with functions like eio_get_last_error.

data

Arbitrary variable passed to callback.

Return Values

eio_grp returns request group resource on success, or false on failure.

Examples

Example #1 eio_grp example

<?php
$temp_filename = dirname(__FILE__) ."/eio-file.tmp";
$fp = fopen($temp_filename, "w");
fwrite($fp, "some data");
fclose($fp);
$my_file_fd = NULL;

/* Is called when the group requests are done */
function my_grp_done($data, $result) {
 // Remove the file, if it still exists
 @unlink($data);
}

/* Is called when the temporary file is opened */
function my_grp_file_opened_callback($data, $result) {
 global $my_file_fd, $grp;

 $my_file_fd = $result;

 $req = eio_read($my_file_fd, 4, 0,
   EIO_PRI_DEFAULT, "my_grp_file_read_callback");
 eio_grp_add($grp, $req);
}

/* Is called when the file is read */
function my_grp_file_read_callback($data, $result) {
 global $my_file_fd, $grp;

 var_dump($result);

 // Create request to close the file
 $req = eio_close($my_file_fd);

 // Add request to the group
 eio_grp_add($grp, $req);
}

// Create request group
$grp = eio_grp("my_grp_done", $temp_filename);

// Create request
$req = eio_open($temp_filename, EIO_O_RDWR | EIO_O_APPEND , NULL,
  EIO_PRI_DEFAULT, "my_grp_file_opened_callback", NULL);

// Add request to the group
eio_grp_add($grp, $req);

// Process requests
eio_event_loop();
?>

The above example will output something similar to:

string(4) "some"

See Also

  • eio_grp_cancel
  • eio_grp_add