chroot
    (PHP 4 >= 4.0.5, PHP 5)
chroot -- Change the root directory
Description
bool 
chroot ( string directory )
   Changes the root directory of the current process to
   directory.
  
   This function is only available if your system supports it and
   you're using the CLI, CGI or Embed SAPI. Also, this function
   requires root privileges.
  
Parameters
   
- directory
 
       The new directory
      
 
  Return Values
   Returns TRUE on success or FALSE on failure.
  
Notes
Note: This function is not
implemented on Windows platforms.