realpath

(PHP 4, PHP 5, PHP 7)

Returns canonicalized absolute pathname

string realpath ( string $path )

realpath() expands all symbolic links and resolves references to '/./', '/../' and extra '/' characters in the input path and returns the canonicalized absolute pathname.

Parameters:

path

The path being checked.

Note:

Whilst a path must be supplied, the value can be blank or NULL In these cases, the value is interpreted as the current directory.

Returns:

Returns the canonicalized absolute pathname on success. The resulting path will have no symbolic link, '/./' or '/../' components. Trailing delimiters, such as \ and /, are also removed.

realpath() returns FALSE on failure, e.g. if the file does not exist.

Note:

The running script must have executable permissions on all directories in the hierarchy, otherwise realpath() will return FALSE.

Note:

For case-insensitive filesystems realpath() may or may not normalize the character case.

Note: Because PHP's integer type is signed and many platforms use 32bit integers, some filesystem functions may return unexpected results for files which are larger than 2GB.

Changelog:

5.3.0

Prior to this release, if only the last path component did not exist, realpath() would not fail on *BSD systems. realpath() now fails in this case.

5.2.1

Prior to this version, realpath() returned FALSE if path is an empty string or NULL.

Examples:

realpath() example

<?php
chdir('/var/www/');
echo realpath('./../../etc/passwd') . PHP_EOL;

echo realpath('/tmp/') . PHP_EOL;
?>

The above example will output:

/etc/passwd
/tmp

realpath() on Windows

On windows realpath() will change unix style paths to windows style.

<?php
echo realpath('/windows/system32');

echo realpath('C:\Program Files\\');
?>

The above example will output:

C:\WINDOWS\System32
C:\Program Files