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 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 */
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); }
See Also
Colophon
This page is part of release 5.04 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.
Referenced By
The man page get_avphys_pages(3) is an alias of get_phys_pages(3).