对非现有文件的PhP触摸返回true

Question

i have a function wich makes a check if a folder is writable. but when i try to use the php touch variable in it like this

public function isFileServerMounted()
{
    $config = $this->getServiceLocator()->get('config');

    $storageDir = $config['xxx']['xxx']['xxx'];
    $mountCheckFile = $config['xxx']['xxx']['xxxx'];

    // we are using a simple file check as indication if we are mounted
    return touch($storageDir . DIRECTORY_SEPARATOR . $mountCheckFile);
}

The function always returns true, regardles if the file i am checking is there or not. i checked the paths and they are correct and i can acess the file via nano over schiell.

The touch comand always returns true, regardles if i delete or make the mount check file.

Anyone has any idea why?

I am using:

PHP 5.3.3-7+squeeze19 with Suhosin-Patch (cli) (built: Feb 17 2014 10:10:23)

Copyright (c) 1997-2009 The PHP Group

Zend Engine v2.3.0, Copyright (c) 1998-2010 Zend Technologies

with Xdebug v2.2.5, Copyright (c) 2002-2014, by Derick Rethans

with Suhosin v0.9.32.1, Copyright (c) 2007-2010, by SektionEins GmbH

OS:

Distributor ID: Debian

Description: Debian GNU/Linux 6.0.3 (squeeze)

Release: 6.0.3

Codename: squeeze

Answer 1

touch() is to sets access and modification time of file.
If the file does not exist, it will be created.

Maybe you can use file_exists like this:

$filename = $storageDir . DIRECTORY_SEPARATOR . $mountCheckFile;

if (!file_exists($filename))
    return false;

return touch($filename);