idle − make process 0 idle

#include <unistd.h>

int idle(void);

idle is an internal system call used during bootstrap. It marks the process’s pages as swappable, lowers its priority, and enters the main scheduling loop. idle never returns.

Only process 0 may call idle. Any user process, even a process with super-user permission, will receive EPERM.

idle never returns for process 0, and always returns −1 for a user process.

EPERM

Always, for a user process.

This function is Linux-specific, and should not be used in programs intended to be portable.

Since 2.3.13 this system call does not exist anymore.