get_phys_pages - Online Linux Manual Page

Section : 3
Updated : 2022-10-30
Source : Linux man-pages 6.03

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 available physical pages of memory on the system.

RETURN VALUE

On success, these functions return a nonnegative value as given in DESCRIPTION. 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 sysinfo(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); }