idle - make process 0 idle
idle is an internal system call used during bootstrap. It
marks the process's pages as swappable, lowers its prior
ity, and enters the main scheduling loop. idle never
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.