.\" Hey Emacs! This file is -*- nroff -*- source.
.\"
.\" Copyright (C) 1996 Andries Brouwer (aeb@cwi.nl)
.\"
.\" 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.\" manual page may be incorrect or out-of-date.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.
.\"
.\" Modified 1997-01-31 by Eric S. Raymond <esr@thyrsus.com>
.\" Modified 2000-03-25 by Jim Van Zandt <jrv@vanzandt.mv.com>
.\" Modified 2001-10-04 by John Levon <moz@compsoc.man.ac.uk>
.\" Modified 2003-02-02 by Andi Kleen <ak@muc.de>
.\" Modified 2003-05-21 by Michael Kerrisk <mtk-manpages@gmx.net>
.\"	MAP_LOCKED works from 2.5.37
.\" Modified 2004-06-17 by Michael Kerrisk <mtk-manpages@gmx.net>
.\" Modified 2004-09-11 by aeb
.\" Modified 2004-12-08, from Eric Estievenart <eric.estievenart@free.fr>
.\" Modified 2004-12-08, mtk, formatting tidy-ups
.\"
.\" Japanese Version Copyright (c) 1997-2000 SUTO, Mitsuaki and NAKANO Takeo
.\"         all rights reserved.
.\" Translated Thu Jun 26 21:00:25 JST 1997
.\"         by SUTO, Mitsuaki <suto@av.crl.sony.co.jp>
.\" Updated & Modified Mon Mar 1 1999
.\"         by NAKANO Takeo <nakano@apm.seikei.ac.jp>
.\" Updated Thu Oct 12 2000 by Nakano Takeo
.\" Updated Thu Aug 16 2001 by Nakano Takeo
.\" Updated Sun Nov 11 2001 by Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\" Updated Tue Aug 13 2002 by Akihiro MOTOKI
.\" Updated Thu Jul  2 2003 by Akihiro MOTOKI
.\" Updated Sun Sep 14 2003 by Akihiro MOTOKI
.\" Updated & Modified Tue Dec 28 05:43:51 JST 2004
.\"         by Yuichi SATO <ysato444@yahoo.co.jp>
.\"
.\"WORD		file descriptor		ե뵭һ
.\"
.TH MMAP 2 2004-12-08 "Linux 2.6.9" "Linux Programmer's Manual"
.SH ̾
mmap, munmap \- եǥХ˥ޥå/ޥåפ
.SH 
.B #include <sys/mman.h>
.sp
.BI "void * mmap(void *" start ", size_t " length ", int " prot
.BI ", int " flags ", int " fd ", off_t " offset );
.sp
.BI "int munmap(void *" start ", size_t " length );
.SH 
.BR mmap ()
ؿϡե뵭һ (file descriptor)
.I fd
ǻꤵ줿ե (⤷Ϥ¾Υ֥) Ρեå
.I offset

.I length
ХȤϰϤ˥ޥåפ (ĥդ) 
ΤȤʤ٤
.IR start
ɥ쥹Ϥ褦˥ޥåפ롣ºݤˤϡΥɥ쥹ϴؿ
ФƤΥҥȤǤʤ̾ 0 ꤹ롣
ºݤ˥֥Ȥޥåפ줿ɥ쥹
.BR mmap ()
֤ͤȤʤꡢ褷 0 ˤϤʤ뤳ȤϤʤ
.LP

.I prot
ˤϡݸɤΤ褦˹Ԥʤꤹ
(եΥץ⡼ɤ̷⤷ƤϤʤ)
.I prot
ˤϡ
.B PROT_NONE
ޤ
¾ PROT_* ե饰ҤȤİʾ塢ӥå OR 黻Τ
줫ꤹ뤳ȤǤ롣
.TP 1.1i
.B PROT_EXEC
ڡϼ¹ԲǽǤ롣
.TP
.B PROT_READ
ڡɤ߹߲ǽǤ롣
.TP
.B PROT_WRITE
ڡ˽񤭹߲ǽǤ롣
.TP
.B PROT_NONE
ڡˤϥǤʤ
.LP

.I flags
ˤϡޥåפ줿֥ȤΥסޥå׻Υץ
ޥåפ줿ڡԡؤѹ
ΥץԤΤ (Ȥ¾ΥץǽʤΤ)
ꤹ롣
ʲ˼ӥåȥǡǤ롣
.TP 1.1i
.B MAP_FIXED
ꤵ줿ɥ쥹ʳΥɥ쥹˥ޥåԥ󥰤Ԥʤʤ
.B start

.B len
ǻꤵ줿ΰ褬¸Υޥåԥ󥰤ΥڡȽŤʤ硢
¸Υޥåԥ󥰤νŤʤäʬϼΤƤ롣
⤷ꤵ줿ɥ쥹ѤǤʤ硢
.B mmap
ϼԤ롣MAP_FIXED ꤷ
.I start
ϥڡܿǤʤƤϤʤ
ΥץϻѤʤɤ
.TP
.B MAP_SHARED
Υޥåԥ󥰤򡢤Υ֥Ȥޥåפ¾ƤΥץȶͭ롣
ΰؤ¸ϡեؤν񤭹ߤǤ롣
ե뤬ºݤ˹Τϡ
.BR msync (2)
ޤ
.BR munmap (2)
ƤФ줿ȤǤ롣
.TP
.B MAP_PRIVATE
ץ饤١Ȥ copy-on-write (񤭹߻ԡ) ޥåפ롣
ΰؤν񤭹ߤϡꥸʥΥե˱ƶʤ
.BR mmap ()
θƤӽФ˥ꥸʥΥեФƹԤ줿ѹ
ޥåΰȿǤ뤫ɤϵꤵƤʤ
.LP
MAP_SHARED  MAP_PRIVATE ϡɬɤ餫ҤȤĤ
ꤷʤФʤʤ
.LP
嵭 3 ĤΥե饰 POSIX.1b ( POSIX.4)  SUSv2 ǵꤵƤ롣
ˡLinux ǤϰʲɸΥե饰Ѥ뤳ȤǤ롣
.TP
.B MAP_DENYWRITE
Υե饰̵뤵롣
.\" 1.1.36 Ƴ졢1.3.24 Ǻ줿
(äϡޥå׸Υեؤν񤭹ߤԤȤȡ顼 ETXTBUSY 
Ԥ褦˥ʥ뤬ꤵƤ denial-of-service
(ӥ)θȤʤä)
.TP
.B MAP_EXECUTABLE
Υե饰̵뤵롣
.\" 1.1.38 Ƴ졢1.3.24 Ǻ줿
.\" proc_follow_link ǥƥȤե饰Ǥ롣(äϡ
.\" ޥå׸Υե뤬¹ԲǽǤ뤳ȤΤ餻褦ˤʤäƤ
.\" ξϼºݤˤϤɤǤȤʤä)
.\" Linus  MAP_EXECUTABLE ˴Ϣ DoS ä򤷤
.\" MAP_DENYWRITE ΤȤͤƤΤʡ
.TP
.B MAP_NORESERVE
(MAP_PRIVATE Ȱ˻Ѥ롣) Υޥåԥ󥰤Ф륹å׶֤
ڡͽԤʤå׶֤ͽ󤷤ϡΥץ饤١Ȥ
copy-on-write (񤭹߻ԡ)ΰѹɬ뤳Ȥݾڤ롣
ͽԤʤäϡ˶ʤȽ񤭹߻ SIGSEGV 顼
뤳Ȥ롣
.TP
.BR MAP_LOCKED " (Linux 2.5.37 ʹ)"
ޥåפ줿ΰΥڡ
.BR mlock ()
ˡǥ˥å롣
ΥͥǤϡΥե饰̵뤵롣
.\" Υե饰åȤƤȡޥåԥ󥰤줿ڡϥåץ
.\" ʤ
.TP
.B MAP_GROWSDOWN
åѤ˻Ѥ롣ޥåԥ󥰤ǵո˹ԤȤ
ͥ VM ƥ˻ؼ롣
(ޥåԥ󥰤̾ϥꡦɥ쥹ä˹Ԥ
Υץꤹȵո˥ޥåԥ󥰤Ԥ)
.TP
.B MAP_ANONYMOUS
ޥåԥ󥰤ϤɤΥեȤϢդʤ

.I fd

.I offset
̵뤵롣MAP_SHARED Ȥ߹碌ƻȤ뤳Υե饰μ
Linux 2.4 ʹߤǹԤƤ롣
.TP
.B MAP_ANON
MAP_ANONYMOUS ̾侩
.TP
.B MAP_FILE
ߴΤΥե饰̵뤵롣
.TP
.B MAP_32BIT
ޥåԥ󥰤ץΥɥ쥹֤Ƭ 2GB ϰϤ֤롣
.I MAP_FIXED
åȤƤϡΥե饰̵뤵롣
ߤΤȤΥե饰ݡȤƤΤϡx86-64 ƥ
 64 ӥåȡץˤĤƤΤߤǤ롣
.TP
.BR MAP_POPULATE " (Linux 2.5.46 ʹ)"
ڡơ֥ (populate) 
(äƥڡեȤ (prefault))
.TP
.BR MAP_NONBLOCK " (Linux 2.5.46 ʹ)"
IO ֥åʤ
.LP
ĤΥƥǤϡ嵭ʳ˥ե饰Ȥ MAP_AUTOGROW, MAP_AUTORESRV,
MAP_COPY, MAP_LOCAL ܤƤ롣
.LP
MAP_ANONYMOUS åȤʤä硢
.I fd
ͭʥե뵭һҤǤʤФʤʤ
MAP_ANONYMOUS åȤ줿ϡ
.I fd
̵뤵롣
.LP
.I offset

.BR getpagesize (2)
֤ڡܤǤʤФʤʤ
.LP
.BR mmap ()
ˤäƥޥåפ줿°
.BR fork (2)
κݤ˷Ѿ롣
.LP
եϥڡܤΰ˥ޥåפ롣ڡ
ܤǤʤեξ硢ޥå׻˻Ĥΰ 0 졢ΰ
񤭤ߤԤäƤե˽񤭽Ф뤳ȤϤʤޥåԥ󥰤Ԥä
եΥѹ硢եɲä줿줿ΰб
ޥåפ줿ڡФƤɤΤ褦ʱƶ뤫ϵꤵƤʤ
ƥॳ
.BR munmap ()
ϻꤵ줿ɥ쥹ϰϤΥޥåפõ
ʹߤΤϰؤΥ껲ȤȤʤ롣
ΰϡץλȤˤ⼫ưŪ˥ޥåפ롣
ե뵭һҤ򥯥Ƥ⡢ΰϥޥåפʤ
.LP
.I start
ɥ쥹ϥڡܤǤʤФʤʤꤵ줿ϰϤΰʬ
ޤƤΥڡϥޥåפ졢ʹߤˤΥڡؤλȤ 
SIGSEGV ȯ롣
ꤷϰ˥ޥåפ줿ڡĤޤޤƤʤǤ
顼ˤʤʤ
եȴϢդ줿ޥåԥ󥰤ξ硢ޥåԥ󥰤줿ե
.B st_atime
եɤϡ
.BR mmap ()
Ƥ饢ޥå (unmap) ޤǤδ֤˹뤳Ȥ롣
ޤǤ˹ԤƤʤСޥåפ줿ڡؤκǽλȤä
ݤ˹롣
.LP
PROT_WRITE  MAP_SHARED ξꤷƥޥåפ줿եξ硢
񤭹ߤȡ
.B st_ctime

.B st_mtime
ξեɤϡޥåפ줿ΰؤν񤭹ߤǡ
MS_SYNC ޤ MS_ASYNC ե饰ꤷ
.BR msync ()
ƤФޤǤ˹롣
.SH ֤
.B mmap
ȥޥåפ줿ΰؤΥݥ󥿤֤
Ԥ
.B MAP_FAILED
(Ĥޤ (void *) \-1) ֤
.I errno
顼ƤˤäƥåȤ롣
.BR munmap ()
 0 ֤Ԥ \-1 ֤
.I errno
åȤ (¿ξ EINVAL ˤʤ)
.SH 
.I PROT_READ

.I PROT_EXEC
ޤޤ뤫ɤϡƥ¸Ǥ롣
ܿθץǤϡ
˥ޥåפΰǥɤ¹Ԥϡ
.I PROT_EXEC
򥻥åȤ٤Ǥ롣
.SH 顼
.TP
.B EACCES
ʲΤ줫ξ硣
ե뵭һҤλ褬̾ΥեǤϤʤ (non-regular file) 
MAP_PRIVATE ׵ᤷ
.I fd
ɤ߹Ѥ˥ץ󤵤Ƥʤ
MAP_SHARED ׵ᤷ PROT_WRITE 򥻥åȤ
.I fd
ɤ߽񤭥⡼ (O_RDWR) ǥץ󤵤Ƥʤ
PROT_WRITE 򥻥åȤեɲ (append) ѤǤ롣
.TP
.B EAGAIN
ե뤬åƤ롣ޤϥåƤ꤬¿
.RB ( setrlimit (2)
򻲾)
.TP
.B EBADF
.I fd
ͭʥե뵭һ (file descriptor) ǤϤʤ
( MAP_ANONYMOUS åȤƤʤ)
.TP
.B EINVAL
.I start

.I length

.IR offset 
ŬڤǤʤ
(㤨С礭ȤPAGESIZE ˥饤ȤƤʤʤ)
.\" jbl - 줬ºݤ˵뤫ɤʬʤgeneric_file_mmap 򸫤衣
.TP
.B ENFILE
.\" ϶ͭƿ̾ (anonymous) ȤΤΤΤǤ롣
.\" [2.6.7] shmem_zero_setup()-->shmem_file_setup()-->get_empty_filp()
ץ󤵤줿եƥ¤ã
.\" .TP
.\" .B ENOEXEC
.\" եɤ߹Ѥ˥ޥåפǤʤä
.TP
.B ENODEV
ꤵ줿ե뤬֤Ƥե륷ƥबޥåԥ󥰤򥵥ݡ
Ƥʤ
.TP
.B ENOMEM
˶ʤޤϽΥץΥޥåԥ󥰿Ķᤷ
.TP
.B EPERM
.I prot

.B PROT_EXEC
Ԥ褦˻ꤵƤ뤬
no-exec ǥޥȤ줿ե륷ƥΥե
ޥåΰ褬бƤ롣
.\" (2.4.25 / 2.6.0 ʹ)
.TP
.B ETXTBSY
MAP_DENYWRITE åȤƤ뤬
.I fd
ǻꤵƤ륪֥ȤϽ񤭹Ѥ˳Ƥ롣
.LP
ޥåΰѤݤˡʲΥʥ뤬ȯ뤳Ȥ:
.TP
.B SIGSEGV
ɤ߹Ѥ mmap 줿ΰؽ񤭹ߤԤȤ
.TP
.B SIGBUS
ХåեΤե˴ϢŤƤʤʬ
(㤨Хեۤʬʤɡˤ
¾Υץեڤͤ᤿ʤɤޤޤ)
˥褦Ȥ
.SH 
.BR mmap (),
.BR msync ()
.BR munmap ()
Ѳǽ POSIX ƥǤϡ
.B _POSIX_MAPPED_FILES
 <unistd.h>  0 礭ͤ롣
.RB ( sysconf (3)
⻲ȤΤȡ)
.\" POSIX 1003.1-2001: _POSIX_MAPPED_FILES  -1  0  200112L 
.\" 줫뤳ȤˤʤäƤ롣
.\" -1: Բġ0: sysconf() 䤤碌
.\" glibc Ǥ POSIX_MAPPED_FILES  1 Ƥ롣
.SH 
SVr4, POSIX.1b ( POSIX.4), 4.4BSD, SUSv2
SVr4 ˤϤ ENXIO  ENODEV Υ顼ɤˤĤƤεҤ롣
SUSv2 ˤϤ EMFILE  EOVERFLOW Υ顼ɤˤĤƤεҤ롣
.SH Х
Linux ˤƤϡ嵭 MAP_NORESERVE ǽҤ٤Ƥ褦ݾڤϤʤ
ǥեȤǤϡƥबȤڤäˤϡ
ɤΥץĶλ뤫ʬʤǤ롣
.SH Ϣ
.BR getpagesize (2),
.BR mlock (2),
.BR mmap2 (2),
.BR mremap (2),
.BR msync (2),
.BR setrlimit (2),
.BR shm_open (2)
.br
B.O. Gallmeister, POSIX.4, O'Reilly, pp. 128-129 and 389-391.
.\"
.\" θˤĤƸäƤߤ: ץ饤١Ȥɤ߹ѤΥޥåԥ󥰤
.\" ͭ줿ɤ߹ѤΥޥåԥ󥰤 100% 
.\" ֤⤷פ֤פ֤֤פʤ-- Linus