NAME | LIBRARY | SYNOPSIS | DESCRIPTION | VERSIONS | STANDARDS | HISTORY | SEE ALSO | COLOPHON |
|
|
getpagesize(2) System Calls Manual getpagesize(2)
getpagesize - get memory page size
Standard C library (libc, -lc)
#include <unistd.h> int getpagesize(void); Feature Test Macro Requirements for glibc (see feature_test_macros(7)): getpagesize(): Since glibc 2.20: _DEFAULT_SOURCE || ! (_POSIX_C_SOURCE >= 200112L) glibc 2.12 to glibc 2.19: _BSD_SOURCE || ! (_POSIX_C_SOURCE >= 200112L) Before glibc 2.12: _BSD_SOURCE || _XOPEN_SOURCE >= 500
The function getpagesize() returns the number of bytes in a memory page, where "page" is a fixed-length block, the unit for memory allocation and file mapping performed by mmap(2).
A user program should not hard-code a page size, neither as a literal nor using the PAGE_SIZE macro, because some architectures support multiple page sizes. This manual page is in section 2 because Alpha, SPARC, and SPARC64 all have a Linux system call getpagesize() though other architectures do not, and use the ELF auxiliary vector instead.
None.
This call first appeared in 4.2BSD. SVr4, 4.4BSD, SUSv2. In SUSv2 the getpagesize() call was labeled LEGACY, and it was removed in POSIX.1-2001. glibc 2.0 returned a constant even on architectures with multiple page sizes.
mmap(2), sysconf(3)
This page is part of the man-pages (Linux kernel and C library
user-space interface documentation) project. Information about
the project can be found at
⟨https://www.kernel.org/doc/man-pages/⟩. If you have a bug report
for this manual page, see
⟨https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTING⟩.
This page was obtained from the tarball man-pages-6.9.1.tar.gz
fetched from
⟨https://mirrors.edge.kernel.org/pub/linux/docs/man-pages/⟩ on
2024-06-26. If you discover any rendering problems in this HTML
version of the page, or you believe there is a better or more up-
to-date source for the page, or you have corrections or
improvements to the information in this COLOPHON (which is not
part of the original manual page), send a mail to
man-pages@man7.org
Linux man-pages 6.9.1 2024-05-02 getpagesize(2)
Pages that refer to this page: fincore(1), strace(1), mmap2(2), mmap(2), mremap(2), remap_file_pages(2), syscalls(2), numa(3), posix_memalign(3)