posix_mkfifo() creates a special FIFO file which exists in the file system and acts as a bidirectional communication endpoint for processes.
pathname
Path to the FIFO file.
mode
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).
Bemærk: Når safe mode er aktiveret, checker PHP om filerne eller bibliotekerne som du er ved at benytte, har det samme UID (owner) som scriptet der bliver eksekveret.