sched_getcpu(3) - BetterMan

sched_getcpu(3)

determine CPU on which the calling thread is running

distropkg manpages-dev@6.9.1-1dataset 2026-04-01T06:19:02Z+debian+ec4110e+mandoc:1.14.6-4

Synopsis

#include <sched.h>
int sched_getcpu(void);
sched_getcpu
():
Since glibc 2.14:
        _GNU_SOURCE
    Before glibc 2.14:
        _BSD_SOURCE || _SVID_SOURCE
            /* _GNU_SOURCE also suffices */

—

Options · 1

ENOSYS

This kernel does not implement getcpu(2).

NAME

sched_getcpu - determine CPU on which the calling thread is running

LIBRARY

Standard C library (libc, -lc)

SYNOPSIS

bash

#include <sched.h>

bash

int sched_getcpu(void);

sched_getcpu():

bash


\n
    Since glibc 2.14:
\n
        _GNU_SOURCE
\n
    Before glibc 2.14:
\n
        _BSD_SOURCE || _SVID_SOURCE
\n
            /* _GNU_SOURCE also suffices */

DESCRIPTION

sched_getcpu() returns the number of the CPU on which the calling thread is currently executing.

RETURN VALUE

On success, sched_getcpu() returns a nonnegative CPU number. On error, -1 is returned and errno is set to indicate the error.

ERRORS

ENOSYS: This kernel does not implement getcpu(2).

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

Interface	Attribute	Value
sched_getcpu ()	Thread safety	MT-Safe

STANDARDS

GNU.

HISTORY

glibc 2.6.

NOTES

The call

bash

cpu = sched_getcpu();

is equivalent to the following getcpu(2) call:

bash

int c, s;
s = getcpu(&c, NULL);
cpu = (s == -1) ? s : c;