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GET_PHYS_PAGES(3) Linux Programmer's Manual GET_PHYS_PAGES(3)

NAME

     get_phys_pages,  get_avphys_pages  -  get  total and available physical
     page counts

SYNOPSIS

     #include <sys/sysinfo.h>

     long int get_phys_pages(void);
     long int 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
     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 MemTo-
     tal 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 */

EXAMPLE

     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); }