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
       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
       GNU.

HISTORY
       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).

NOTES
       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 6.7               2023-10-31                 get_phys_pages(3)