What are some common reasons for the "No such file or directory" error when using mkdir() in PHP?

The "No such file or directory" error in PHP when using mkdir() typically occurs when the specified directory path does not exist or there are permission issues preventing the creation of the directory. To solve this issue, ensure that the parent directories leading to the target directory exist and are writable by the PHP process.

$directory = '/path/to/new/directory';

if (!file_exists($directory)) {
    mkdir($directory, 0777, true);
}