get_nprocs, get_nprocs_conf - get number of processors
#include <sys/sysinfo.h>
int get_nprocs(void);
int get_nprocs_conf(void);
The function get_nprocs_conf() returns the number of processors configured by the operating system.
The function get_nprocs() returns the number of processors currently available in the system. This may be less than the number returned by get_nprocs_conf() because processors may be offline (e.g., on hotpluggable systems).
As given in DESCRIPTION.
The following example shows how get_nprocs() and get_nprocs_conf() can be used.
#include <stdlib.h>
#include <stdio.h>
#include <sys/sysinfo.h>
int
main(int argc, char *argv[])
{
printf("This system has %d processors configured and "
"%d processors available.\n",
get_nprocs_conf(), get_nprocs());
exit(EXIT_SUCCESS);
}
For an explanation of the terms used in this section, see attributes(7).
Interface | Attribute | Value |
get_nprocs(), get_nprocs_conf() |
Thread safety | MT-Safe |
These functions are GNU extensions.
The current implementation of these functions is rather expensive, since they open and parse files in the /sys
filesystem each time they are called.
The following sysconf(3) calls make use of the functions documented on this page to return the same information.
np = sysconf(_SC_NPROCESSORS_CONF); /* processors configured */
np = sysconf(_SC_NPROCESSORS_ONLN); /* processors available */
nproc(1)
This page is part of release 5.10 of the Linux man-pages
project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.