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.\" Copyright (C) Michael Kerrisk, 2004
.\"	using some material drawn from earlier man pages
.\"	written by Thomas Kuhn, Copyright 1996
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.\" Japanese Version Copyright (c) 1997 HANATAKA Shinya
.\"         all rights reserved.
.\" Translated 1997-02-23, HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Updated 2003-10-12, Kentaro Shirakata <argrath@ub32.org>
.\" Updated 2004-05-23, kentaro Shirakata <argrath@ub32.org>
.\" Updated 2005-03-29, kentaro Shirakata <argrath@ub32.org>
.\" Updated 2005-11-04, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\" Updated 2006-02-14, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\"
.\"WORD:	unlock			å
.\"WORD:	previlege		ø
.\"
.TH MLOCK 2 2006-02-04 "Linux" "Linux Programmer's Manual"
.SH ̾
mlock \- ΥåȥåԤ
.SH 
.nf
.B #include <sys/mman.h>
.sp
.BI "int mlock(const void *" addr ", size_t " len );
.BI "int munlock(const void *" addr ", size_t " len );
.sp
.BI "int mlockall(int " flags );
.B int munlockall(void);
.fi
.SH 
.BR mlock ()

.BR mlockall ()
Ϥ줾졢ƤӽФץβۥɥ쥹֤ΰޤ
RAM ˥å꤬åץꥢ˥ڡ󥰤Τɤ
.BR munlock ()

.BR munlockall ()
ϵդǡ줾ƤӽФץβۥɥ쥹֤ΰޤ
å롣Ĥޤꡢꤵ줿ۥɥ쥹ϰϤΥڡ
ͥޥ͡㡼׵ᤵХåץȤ褦ˤʤ롣
Υåȥåϥڡñ̤ǹԤ롣
.SS "mlock()  munlock()"
.BR mlock ()

.I addr
ϤޤĹ
.I len
ХȤΥɥ쥹ϰϤΥڡå롣
ƤӽФˤϡ
ꤵ줿ɥ쥹ϰϤޤƤΥڡ
RAM ˻Ĥ³뤳Ȥݾڤ롣
Υڡϸǥåޤ RAM ˻Ĥ³뤳Ȥݾڤ롣
.SS "mlockall()  munlockall()"
.BR mlockall ()
ϸƤӽФץΥɥ쥹֤˥ޥåפƤƤΥڡ
å롣ˤϥɡǡå
ƥȡͭ饤֥ꡢͥΥ桼֥ǡ
ͭꡢꡦޥåפ줿ե뤬ޤޤ롣
ƥࡦ뤬ˤƤΥޥåפ줿ڡ RAM 
Ĥ뤳Ȥݾڤ롣
Υڡϸǥåޤ RAM ˻Ĥ³뤳Ȥݾڤ롣
.I flags
ϰʲƤΰĤޤʣΥӥå OR 鹽:
.TP 1.2i
.B MCL_CURRENT
ߡץΥɥ쥹֤˥ޥåפƤƤΥڡå롣
.TP
.B MCL_FUTURE
衢ץΥɥ쥹֤˥ޥåפƤΥڡå롣
㤨Сҡ (heap) 䥹åĹˤ꿷ɬפˤʤäڡ
ʤޥåפ줿ե䶦ͭΰå롣
.PP
.B MCL_FUTURE
ꤵƤȡʸΥƥॳ (㤨С
.BR mmap (2),
.BR sbrk (2),
.BR malloc (3))
ϡåХȿĤ줿 () Ķ
Ԥǽ롣
ƱͤˡåĹ⼺Ԥǽ롣
ξ硢ͥϥåγĥݤ
.B SIGSEGV
ץ롣

.BR munlockall ()
ϡƤӽФץΥɥ쥹֤˥ޥåԥ󥰤Ƥ
ƤΥڡå롣
.SH ֤
ϡΥƥॳϥ֤
顼ξ \-1 ֤졢
.I errno
Ŭڤꤵ졢ץΥɥ쥹֤ˤåѹʤ
.SH 顼
.TP
.B ENOMEM
(Linux 2.6.9 ʹ) ƤӽФ󥼥
եȻ
.B RLIMIT_MEMLOCK
Ĥ¤ĤƤʾΥå褦Ȥ
¤ϡץø
.RB ( CAP_IPC_LOCK )
äƤŬѤʤ
.TP
.B ENOMEM
(Linux 2.4 ) ƤӽФץ RAM Ⱦʬʾå褦Ȥ
.TP
.B EPERM
(Linux 2.6.9 ʹ) ƤӽФø
.RB ( CAP_IPC_LOCK )
եȻ
.B RLIMIT_MEMLOCK
 0 Ǥ롣
.TP
.B EPERM
(Linux 2.6.8 )
ƤӽФץ
.BR munlockall ()
ƤӽФΤɬפøͭƤʤä
Linux Ǥϡ
.B CAP_IPC_LOCK
ѥӥƥɬפǤ롣
.\"SVr4 ΥɥȤˤϡʳ˥顼 EAGAIN εܤ롣
.LP
.BR mlock ()

.BR munlock ()
ѤȤ:
.TP
.B EINVAL
.I len
οǤ롣
.TP
.B EINVAL
(Linux ǤϤΰ̣ǻȤʤ)
.I addr
ڡܿǤϤʤ
.TP
.B ENOMEM
ꤵ줿ɥ쥹ϰϤץΥɥ쥹֤˥ޥåפ줿ڡ
פʤ
.LP
.BR mlockall ()
ѤȤ:
.TP
.B EINVAL
̤Τ \fIflags\fP ꤵ줿
.LP
.BR munlockall ()
ѤȤ:
.TP
.B EPERM
(Linux 2.6.8 ) ƤӽФ
.RB ( CAP_IPC_LOCK )
äƤʤ
.SH 
POSIX.1-2001, SVr4
.SH 
.BR mlock ()

.BR munlock ()
Ѳǽ POSIX ƥǤ
.B _POSIX_MEMLOCK_RANGE
 \fI<unistd.h>\fP Ƥ롣
ޤڡΥХȿϡ
<limits.h> 
.B PAGESIZE
 (Ƥ)⤷
.I sysconf(_SC_PAGESIZE)
ƤӽФȤǷǤ롣

.BR mlockall ()

.BR munlockall ()
Ѳǽ POSIX ƥǤϡ
.B _POSIX_MEMLOCK
 \fI<unistd.h>\fP  0 礭ͤƤ
.RB ( sysconf (3)
⻲ȤΤ)
.\" POSIX.1-2001: ѿ -1  0  200112l Τ줫
.\" ٤ȤʤäƤ롣
.\" -1: ѤǤʤ0: sysconf() 䤤碌
.\" glibc Ǥ 1 Ƥ롣
.SH 
ΥåӤȤƤϼĤ: ꥢ륿
르ꥺȹ⤤ƥɬפʥǡǤ롣ꥢ륿
ץꥱϷŪʥߥ󥰤䥹塼󥰤ɬפȤ뤬
ڡ󥰤ͽʤץμ¹ٱ⤿餹פװȤʤ롣
ꥢ륿ΥץꥱϤƤ
.BR sched_setscheduler (2)
ǥꥢ륿ॹ塼ѹ롣
Ź䥻ƥΥեȥϤФХѥɤ̩Υǡ
褦ʽפʥХ򰷤ڡ󥰤η̡̩
åѤθΤž뤫⤷ʤơƥ
եȥ RAM ̩ƽλäȸˤʤäƤ⡢
Υåפ줿ǡˤŨǤǽ
(åץȥåפȤĤΥǥȥåץԥ塼
ڥɥ⡼ɤϥƥ RAM ƤΥå˴ؤ餺
ǥ¸뤳Ȥ)

ꥢ륿ץ
.BR mlockall ()
ȤäƥڡեȤˤٱɤȤ硢
ؿƤӽФˤäƥڡեȤȯʤ褦ˡ
¤θʬ (time-critical section) 
ʬ̤Υå줿åݤƤɬפ롣
¸ˤϡʬ礭μưѿ () ݤ
ΥåѤΥڡ˳ݤ褦ˤ
񤭹ߤԤؿѰդƤӽФФ褤뤳Ȥǡ
ʬ̤Υڡå˥ޥåԥ󥰤졢RAM ˥å롣
ߡν񤭹ߤԤȤˤäơ
¤θʬ (critical section) ǤϽ񤭹߻ԡˤ
ڡեȤȯʤȤݾڤ롣

å
.BR fork (2)
Ǻ줿ҥץˤϷѾ줺
.BR execve (2)
ƤФ줿ꡢץλ
ưŪ˺ (å)

륢ɥ쥹ϰϤФåϡΥɥ쥹ϰϤ
.BR munmap (2)
ˤäƥޥåפ줿Ϻ롣

ΥåѤʤ
ʤʣ
.BR mlock ()

.BR mlockall ()
ƤӽФƥå줿ڡǤ⡢
бϰϤФ
.BR munlock ()
 1 ƤӽФ
.BR munlockall ()
ƤӽФꤹǥå롣
ʣξʣΥץ˥ޥåפƤڡϡʤȤĤξꡢ
ĤΥץǥåƤ¤ RAM ˻Ĥ³롣

.SS Linux Ǥ
Linux Ǥϡ
.BR mlock ()

.BR munlock ()
ϼưŪ
.I addr
üڤΤƤˤֶᤤڡؤȴݤ롣
 POSIX.1-2001 
.I addr
ڡ˹äƤ뤳Ȥ׵᤹Ƥ롣
ΤܿտޤץꥱǤϤȶ˹碌ɤ
.SS ¤ȸ
Linux 2.6.8 Ǥϡå뤿ˤø
.RB ( CAP_IPC_LOCK )
ɬפǡ
եȻ
.B RLIMIT_MEMLOCK
ϥץɤΥåǤ뤫¤롣

Linux 2.6.9 ʹߤǤϡøĥץåǤ̵̤¤Ȥʤꡢ
˥եȻ
.B RLIMIT_MEMLOCK
øʤץåǤ̤¤롣
.SH Х
2.4.17 ޤǤ 2.4 ꡼ Linux ͥˤϡ
.BR mlockall ()
.B MCL_FUTURE
ե饰
.BR fork (2)
ǷѾȸХ롣
ϥͥ 2.4.18 ǽ줿

ͥ 2.6.9 ʹߤǤϡøäץ
.I mlockall(MCL_FUTURE)
ƤӽФǡøʤ (㤨С
¸ UID  0 ʳͤѹʤɤˤꡢ
.B CAP_IPC_LOCK
ѥӥƥ򼺤ä)꥽
.B RLIMIT_MEMLOCK
ãȡʹߤΥ (㤨
.BR mmap (2),
.BR brk (2))
ϼԤ롣
.\" LKML ΰʲΥåɤ򻲾:
.\" http://marc.theaimsgroup.com/?l=linux-kernel&m=113801392825023&w=2
.\" "Rationale for RLIMIT_MEMLOCK"
.\" 23 Jan 2006
.SH Ϣ
.BR mmap (2),
.BR shmctl (2),
.BR setrlimit (2),
.BR sysconf (3),
.BR capabilities (7)