Get_avphys_pages (3) Linux Manual Page

get_phys_pages, get_avphys_pages – get total and available physical page counts

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 cause of the error.

Errors

ENOSYS: The system could not provide the required information (possibly because the /proc filesystem was not mounted).

Conforming To

These functions are GNU extensions.

Notes

These functions obtain the required information by scanning the MemTotal and MemFree fields of /proc/meminfo.

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(int argc, char *argv[]) {
    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); }

Colophon

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get_avphys_pages (3) Linux Manual Page