diff options
Diffstat (limited to 'man/man2/getpagesize.2')
-rw-r--r-- | man/man2/getpagesize.2 | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/man/man2/getpagesize.2 b/man/man2/getpagesize.2 new file mode 100644 index 0000000..1bfcad3 --- /dev/null +++ b/man/man2/getpagesize.2 @@ -0,0 +1,67 @@ +.\" Copyright (C) 2001 Andries Brouwer <aeb@cwi.nl> +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.TH getpagesize 2 2024-05-02 "Linux man-pages (unreleased)" +.SH NAME +getpagesize \- get memory page size +.SH LIBRARY +Standard C library +.RI ( libc ", " \-lc ) +.SH SYNOPSIS +.nf +.B #include <unistd.h> +.P +.B int getpagesize(void); +.fi +.P +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.P +.BR getpagesize (): +.nf + 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 +.\" || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED +.fi +.SH DESCRIPTION +The function +.BR 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 +.BR mmap (2). +.SH VERSIONS +A user program should not hard-code a page size, +neither as a literal nor using the +.B PAGE_SIZE +macro, +because some architectures support multiple page sizes. +.P +This manual page is in section 2 because +Alpha, SPARC, and SPARC64 +all have a Linux system call +.BR getpagesize () +though other architectures do not, +and use the ELF auxiliary vector instead. +.SH STANDARDS +None. +.SH HISTORY +This call first appeared in 4.2BSD. +SVr4, 4.4BSD, SUSv2. +In SUSv2 the +.BR getpagesize () +call was labeled LEGACY, +and it was removed in POSIX.1-2001. +.P +glibc 2.0 returned a constant +even on architectures with multiple page sizes. +.SH SEE ALSO +.BR mmap (2), +.BR sysconf (3) |