(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)
ftok — Convert a pathname and a project identifier to a System V IPC key
$filename, string $project_id): int
The function converts the filename of an existing
accessible file and a project identifier into an
integer for use with for example
shmop_open() and other System V IPC keys.
filenamePath to an accessible file.
project_idProject identifier. This must be a one character string.
On success the return value will be the created key value, otherwise
-1 is returned.