Finding the Apache user in PHP

In PHP, knowing what the Apache user is on your webserver is very useful. Anything that writes a file to the server for example sessions, uploading files or other temporary file operations, needs to have the destination folder writeable by Apache. If you’re developing locally that’s not usually a problem. But as soon as you’re out in the real world file permission issues can sometimes be a pain.

If you’re having difficulties finding out what the Apache user is try this simple script to help you out.

It basically writes a small temporary file, checks the owner username, gets rid of the file and prints the Apache username to the screen. It should work on PHP4 and PHP5.

$tmpFilename = tempnam('/tmp', 'TEST');
$handle = fopen($tmpFilename, 'w');
fwrite($handle, 'testdata');
fclose($handle);
$info = posix_getpwuid(fileowner($tmpFilename));
$apacheUser = $info['name'];
unlink($tmpFilename);
echo "The Apache user is $apacheUser";

There’s also a small PHP source file you can easily download and use: getApacheUser.phps