Sets the current
for a process, a process
group, or a user.
must indicate one of these types:
therefore identifies the specific process, process group, or user
with its ID.
is an integer number that will be added to or
subtracted from the current priority; the lower the number, the higher the
The interpretation of a given priority may vary from one operating system to
on your system.
will produce a fatal error if used on a
machine that doesn't implement