get_phys_pages, get_avphys_pages − get total and available physical page counts
Standard C library (libc, −lc)
#include <sys/sysinfo.h>
long
get_phys_pages(void);
long get_avphys_pages(void);
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.
On success, these functions return a nonnegative value as given in DESCRIPTION. On failure, they return −1 and set errno to indicate the error.
ENOSYS |
The system could not provide the required information (possibly because the /proc filesystem was not mounted). |
GNU.
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
*/
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);
}
sysconf(3)