fileperms in PHP

fileperms — Gets file permissions
Syntax:

int fileperms ( string $filename )
Gets permissions for the given file.

Parameters:

filename
Path to the file.

Return values: Returns the file's permissions as a numeric mode. Lower bits of this mode are the same as the permissions expected by chmod(), however on most platforms the return value will also include information on the type of file given as filename. The examples below demonstrate how to test the return value for specific permissions and file types on POSIX systems, including Linux and Mac OS X.

For local files, the specific return value is that of the st_mode member of the structure returned by the C library's stat() function. Exactly which bits are set can vary from platform to platform, and looking up your specific platform's documentation is recommended if parsing the non-permission bits of the return value is required.



Example #1 Display permissions as an octal value

<?php
echo substr(sprintf('%o', fileperms('/tmp')), -4);
echo substr(sprintf('%o', fileperms('/etc/passwd')), -4);
?>
The above example will output:

1777
0644
Example #2 Display full permissions

<?php
$perms = fileperms('/etc/passwd');

if (($perms & 0xC000) == 0xC000) {
    // Socket
    $info = 's';
} elseif (($perms & 0xA000) == 0xA000) {
    // Symbolic Link
    $info = 'l';
} elseif (($perms & 0x8000) == 0x8000) {
    // Regular
    $info = '-';
} elseif (($perms & 0x6000) == 0x6000) {
    // Block special
    $info = 'b';
} elseif (($perms & 0x4000) == 0x4000) {
    // Directory
    $info = 'd';
} elseif (($perms & 0x2000) == 0x2000) {
    // Character special
    $info = 'c';
} elseif (($perms & 0x1000) == 0x1000) {
    // FIFO pipe
    $info = 'p';
} else {
    // Unknown
    $info = 'u';
}

// Owner
$info .= (($perms & 0x0100) ? 'r' : '-');
$info .= (($perms & 0x0080) ? 'w' : '-');
$info .= (($perms & 0x0040) ?
            (($perms & 0x0800) ? 's' : 'x' ) :
            (($perms & 0x0800) ? 'S' : '-'));

// Group
$info .= (($perms & 0x0020) ? 'r' : '-');
$info .= (($perms & 0x0010) ? 'w' : '-');
$info .= (($perms & 0x0008) ?
            (($perms & 0x0400) ? 's' : 'x' ) :
            (($perms & 0x0400) ? 'S' : '-'));

// World
$info .= (($perms & 0x0004) ? 'r' : '-');
$info .= (($perms & 0x0002) ? 'w' : '-');
$info .= (($perms & 0x0001) ?
            (($perms & 0x0200) ? 't' : 'x' ) :
            (($perms & 0x0200) ? 'T' : '-'));

echo $info;
?>
The above example will output:

-rw-r--r--
Errors/Exceptions ¶

Upon failure, an E_WARNING is emitted.



Note: The results of this function are cached. See clearstatcache() for more details.
Tip
As of PHP 5.0.0, this function can also be used with some URL wrappers. Refer to Supported Protocols and Wrappers to determine which wrappers support stat() family of functionality.