+++ /dev/null
-.\" Copyright (C) 2001 Andries Brouwer <aeb@cwi.nl>
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" Permission is granted to make and distribute verbatim copies of this
-.\" manual provided the copyright notice and this permission notice are
-.\" preserved on all copies.
-.\"
-.\" Permission is granted to copy and distribute modified versions of this
-.\" manual under the conditions for verbatim copying, provided that the
-.\" entire resulting derived work is distributed under the terms of a
-.\" permission notice identical to this one.
-.\"
-.\" Since the Linux kernel and libraries are constantly changing, this
-.\" manual page may be incorrect or out-of-date. The author(s) assume no
-.\" responsibility for errors or omissions, or for damages resulting from
-.\" the use of the information contained herein. The author(s) may not
-.\" have taken the same level of care in the production of this manual,
-.\" which is licensed free of charge, as they might when working
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.TH GETPAGESIZE 2 2014-08-19 "Linux" "Linux Programmer's Manual"
-.SH NAME
-getpagesize \- get memory page size
-.SH SYNOPSIS
-.B #include <unistd.h>
-.sp
-.B int getpagesize(void);
-.sp
-.in -4n
-Feature Test Macro Requirements for glibc (see
-.BR feature_test_macros (7)):
-.in
-.sp
-.BR getpagesize ():
-.ad l
-.RS 4
-.PD 0
-.TP 4
-Since glibc 2.12:
-.nf
-_BSD_SOURCE ||
- !(_POSIX_C_SOURCE\ >=\ 200112L || _XOPEN_SOURCE\ >=\ 600)
-.TP 4
-.fi
-Before glibc 2.12:
-_BSD_SOURCE || _XOPEN_SOURCE\ >=\ 500 ||
-_XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED
-.PD
-.RE
-.ad b
-.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 HISTORY
-.\" This call first appeared in 4.2BSD.
-.SH CONFORMING TO
-SVr4, 4.4BSD, SUSv2.
-In SUSv2 the
-.BR getpagesize ()
-call is labeled LEGACY, and in POSIX.1-2001
-it has been dropped;
-HP-UX does not have this call.
-.SH NOTES
-Portable applications should employ
-.I sysconf(_SC_PAGESIZE)
-instead of
-.BR getpagesize ():
-.PP
-.in +4n
-.nf
-#include <unistd.h>
-long sz = sysconf(_SC_PAGESIZE);
-.fi
-.in
-
-(Most systems allow the synonym
-.B _SC_PAGE_SIZE
-for
-.BR _SC_PAGESIZE .)
-
-Whether
-.BR getpagesize ()
-is present as a Linux system call depends on the architecture.
-If it is, it returns the kernel symbol
-.BR PAGE_SIZE ,
-whose value depends on the architecture and machine model.
-Generally, one uses binaries that are dependent on the architecture but not
-on the machine model, in order to have a single binary
-distribution per architecture.
-This means that a user program
-should not find
-.B PAGE_SIZE
-at compile time from a header file,
-but use an actual system call, at least for those architectures
-(like sun4) where this dependency exists.
-Here glibc 2.0 fails because its
-.BR getpagesize ()
-returns a statically derived value, and does not use a system call.
-Things are OK in glibc 2.1.
-.SH SEE ALSO
-.BR mmap (2),
-.BR sysconf (3)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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