eio_grp_limit
eio_init
Eio Functions
PHP Manual

# eio_grp

Createsa 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 error.

### 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