idle(2) — Linux manual page

NAME \| SYNOPSIS \| DESCRIPTION \| RETURN VALUE \| ERRORS \| STANDARDS \| HISTORY \| COLOPHON

idle(2)                    System Calls Manual                    idle(2)

NAME top

       idle - make process 0 idle

SYNOPSIS top

       #include <unistd.h>

       [[deprecated]] int idle(void);

DESCRIPTION top

       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 superuser permission, will receive EPERM.

RETURN VALUE top

       idle() never returns for process 0, and always returns -1 for a
       user process.

ERRORS top

       EPERM  Always, for a user process.

STANDARDS top

       Linux.

HISTORY top

       Removed in Linux 2.3.13.

COLOPHON top

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Linux man-pages 6.15            2025-05-17                        idle(2)

Pages that refer to this page: syscalls(2)