(PHP 3 >= 3.0.13, PHP 4, PHP 5)
posix_mkfifo -- 
     Create a fifo special file (a named pipe)
    
Description
bool 
posix_mkfifo ( string pathname, int mode )
     posix_mkfifo() creates a special
     FIFO file which exists in the file system and acts as
     a bidirectional communication endpoint for processes.
    
     The second parameter mode has to be given in octal
     notation (e.g. 0644). The permission of the newly created
     FIFO also depends on the setting of the current
     umask(). The permissions of the created file are (mode
     & ~umask).
    
     Returns TRUE on success or FALSE on failure.
    
Note: When safe mode is enabled, PHP checks whether 
the directory in which you are about to operate has the same UID (owner) as the 
script that is being executed.