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eio_readlink

(PECL eio >= 0.0.1dev)

eio_readlink — Read value of a symbolic link

Description

eio_readlink(
    string $path,
    int $pri,
    callable $callback,
    mixed $data = NULL
): resource

Parameters

path

Source symbolic link path

pri

The request priority: EIO_PRI_DEFAULT, EIO_PRI_MIN, EIO_PRI_MAX, or null. If null passed, pri internally is set to EIO_PRI_DEFAULT.

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_readlink() returns request resource on success, or false on failure.

Examples

Example #1 eio_readlink() example

<?php
$filename
= dirname(__FILE__)."/symlink.dat";
touch($filename);
$link = dirname(__FILE__)."/symlink.link";
$hardlink = dirname(__FILE__)."/hardlink.link";

function
my_hardlink_cb($data, $result) {
global
$link, $filename;
var_dump(file_exists($data) && !is_link($data));
@
unlink($data);

eio_symlink($filename, $link, EIO_PRI_DEFAULT, "my_symlink_cb", $link);
}

function
my_symlink_cb($data, $result) {
global
$link, $filename;
var_dump(file_exists($data) && is_link($data));

if (!
eio_readlink($data, EIO_PRI_DEFAULT, "my_readlink_cb", NULL)) {
@
unlink($link);
@
unlink($filename);
}
}

function
my_readlink_cb($data, $result) {
global
$filename, $link;
var_dump($result);

@
unlink($link);
@
unlink($filename);
}

eio_link($filename, $hardlink, EIO_PRI_DEFAULT, "my_hardlink_cb", $hardlink);
eio_event_loop();
?>

The above example will output something similar to:

bool(true)
bool(true)
string(16) "/tmp/symlink.dat"

See Also

  • eio_symlink() - Create a symbolic link