Description
string 
php_uname ( [string mode] )
     php_uname() returns a description of the operating
     system PHP is running on. For the name of just the operating system,
     consider using the PHP_OS constant, but be
     reminded this constant will contain the operating system PHP was
     built on.
    
     On Unix, the output reverts to displaying the operating system
     information PHP was built on if it cannot determine the currently
     running OS.
    
     mode is a single character that defines what
     information is returned:
     
- 
        'a': This is the default. Contains all modes in the sequence "s n r v m".
        
- 
        's': Operating system name. eg. FreeBSD.
        
- 
        'n': Host name. eg. localhost.example.com.
        
- 
        'r': Release name. eg. 5.1.2-RELEASE.
        
- 
        'v': Version information. Varies a lot between operating systems.
        
- 
        'm': Machine type. eg. i386.
        
     
| Example 1. Some php_uname() examples | 
<?phpecho php_uname();
 echo PHP_OS;
 
 /* Some possible outputs:
 Linux localhost 2.4.21-0.13mdk #1 Fri Mar 14 15:08:06 EST 2003 i686
 Linux
 
 FreeBSD localhost 3.2-RELEASE #15: Mon Dec 17 08:46:02 GMT 2001
 FreeBSD
 
 Windows NT XN1 5.1 build 2600
 WINNT
 */
 
 if (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN') {
 echo 'This is a server using Windows!';
 } else {
 echo 'This is a server not using Windows!';
 }
 
 ?>
 | 
 | 
    
     There are also some related 
     Predefined PHP
     constants that may come in handy, for example:
    
     
| Example 2. A few OS related constant examples | 
<?php// *nix
 echo DIRECTORY_SEPARATOR; // /
 echo PHP_SHLIB_SUFFIX;    // so
 echo PATH_SEPARATOR;      // :
 
 // Win*
 echo DIRECTORY_SEPARATOR; // \
 echo PHP_SHLIB_SUFFIX;    // dll
 echo PATH_SEPARATOR;      // ;
 ?>
 | 
 | 
    
     See also phpversion(), 
     php_sapi_name(), and 
     phpinfo().