get_phys_pages(3) Library Functions Manual get_phys_pages(3)
NAME
get_phys_pages, get_avphys_pages - get total and available physical
page counts
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <sys/sysinfo.h>
long get_phys_pages(void);
long get_avphys_pages(void);
DESCRIPTION
The function get_phys_pages() returns the total number of physical
pages of memory available on the system.
The function get_avphys_pages() returns the number of currently avail-
able physical pages of memory on the system.
RETURN VALUE
On success, these functions return a nonnegative value as given in DE-
SCRIPTION. On failure, they return -1 and set errno to indicate the
error.
ERRORS
ENOSYS The system could not provide the required information (possibly
because the /proc filesystem was not mounted).
STANDARDS
These functions are GNU extensions.
NOTES
Before glibc 2.23, these functions obtained the required information by
scanning the MemTotal and MemFree fields of /proc/meminfo. Since glibc
2.23, these functions obtain the required information by calling sys-
info(2).
The following sysconf(3) calls provide a portable means of obtaining
the same information as the functions described on this page.
total_pages = sysconf(_SC_PHYS_PAGES); /* total pages */
avl_pages = sysconf(_SC_AVPHYS_PAGES); /* available pages */
EXAMPLES
The following example shows how get_phys_pages() and get_avphys_pages()
can be used.
#include <stdio.h>
#include <stdlib.h>
#include <sys/sysinfo.h>
int
main(void)
{
printf("This system has %ld pages of physical memory and "
"%ld pages of physical memory available.\n",
get_phys_pages(), get_avphys_pages());
exit(EXIT_SUCCESS);
}
SEE ALSO
sysconf(3)
Linux man-pages 6.03 2022-10-30 get_phys_pages(3)
Generated by dwww version 1.15 on Mon Jun 24 14:19:18 CEST 2024.