Making New Directories (PHP Cookbook)

19.11.3. Discussion

The second argument to mkdir( ) is the permission mode for the new directory, which must be an octal number. The current umask is taken away from this permission value to create the permissions for the new directory. So, if the current umask is 0002, calling mkdir('/tmp/apples',0777) sets the permissions on the resulting directory to 0775 (user and group can read, write, and execute; others can only read and execute).

PHP's built-in mkdir( ) can make a directory only if its parent exists. For example, if /tmp/a doesn't exist, you can't create /tmp/a/b until /tmp/a is created. To create a directory and its parents, you have two choices: you can call your system's mkdir program, or you can use the pc_mkdir_parents( ) function, shown in Example 19-3. To use your system's mkdir program, on Unix, use this:

system('/bin/mkdir -p '.escapeshellarg($directory));

On Windows do:

system('mkdir '.escapeshellarg($directory));

You can also use the pc_mkdir_parents( ) function shown in Example 19-3.

Example 19-3. pc_mkdir_parents( )

function pc_mkdir_parents($d,$umask = 0777) {
    $dirs = array($d);
    $d = dirname($d);
    $last_dirname = '';
    while($last_dirname != $d) { 
        array_unshift($dirs,$d);
        $last_dirname = $d;
        $d = dirname($d);
    }

    foreach ($dirs as $dir) {
        if (! file_exists($dir)) {
            if (! mkdir($dir,$umask)) {
                error_log("Can't make directory: $dir");
                return false;
            }
        } elseif (! is_dir($dir)) {
            error_log("$dir is not a directory");
            return false;
        }
    }
    return true;
}

For example:

pc_mkdir_parents('/usr/local/upload/test',0777);

Example 19-3. pc_mkdir_parents( )

19.11. Making New Directories

19.11.1. Problem

19.11.2. Solution

19.11.3. Discussion

19.11.4. See Also