Home Contents | # os.nice | OS | Core4 Lua Commands

## SYNOPSIS

#include <lua/signal.lh>
os.nice([delta])

## DESCRIPTION

Change current process priority by adding delta to the current priority. (A higher nice value means a lower priority.)

The range of the resulting priority is +19 (low priority) to -20 (high priority).

To read current nice value, pass 0 or no value at all.

A spawned process inherits the parent's nice value at the time of spawning. Afterwards, the nice values are handled separately.

## CAVEATS

Core4 has a simple scheduler. The lowest nice value that wants to run wins. Setting nice too low can prevent important kernel tasks from running.

## RETURN VALUE

On success, returns current process nice value. On error, three values are returned: nil, a string describing the error (The result of the C library call strerror() on the errno code) and the errno number from the standard C library.