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.\" Copyright 1993 Rickard E. Faith (faith@cs.unc.edu) and
.\" and Copyright 2002 Michael Kerrisk
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.\" Modified Fri Jan 31 16:26:07 1997 by Eric S. Raymond <esr@thyrsus.com>
.\" Modified Fri Dec 11 17:57:27 1998 by Jamie Lokier <jamie@imbolc.ucc.ie>
.\" Modified 24 Apr 2002 by Michael Kerrisk <mtk.manpages@gmail.com>
.\"	Substantial rewrites and additions
.\" 2005-05-10 mtk, noted that lock conversions are not atomic.
.\"
.\" Japanese Version Copyright (c) 1996 Takeshi Ueno
.\"         all rights reserved.
.\" Translated 1996-07-03, Takeshi Ueno <tueno@vio.co.jp>
.\" Modified 1997-12-14, HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Modified 1999-08-14, HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Modified 2002-09-24, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\" Modified 2005-02-26, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\" Updated 2005-09-06, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\"
.TH FLOCK 2 2002-04-24 "Linux" "Linux Programmer's Manual"
.SH ̾
flock \- ץ󤵤줿եФ륢ɥХꡦåŬѡԤ
.SH 
.B #include <sys/file.h>
.sp
.BI "int flock(int " fd ", int " operation );
.SH 
ץ󤵤줿ե˥ɥХꡦå(advisory lock)Ŭ
Ԥ
ե
.I fd
ǻꤹ롣
.I operation
ˤϰʲΤ줫Ĥꤹ:
.RS 4
.TP 9
.B LOCK_SH
ͭåŬѤ롣 ꤷեФơ
İʾΥץƱ˶ͭåݻ뤳ȤǤ롣
.TP
.B LOCK_EX
¾åŬѤ롣  ꤷեФơ
ĤΥץƱ¾åݻ뤳ȤǤ롣
.TP
.B LOCK_UN
ΥץݻƤ¸Υå롣
.RE
.PP
.BR flock ()
ƤӽФȤˡꤷå̤Ȱۤʤḁ̊ץˤä
ݻƤȡ
.BR flock ()
 (block) 뤳Ȥ롣
 (non-blocking) פ׵Ԥˤϡ
嵭 (operation) 
.B LOCK_NB
¤ηǻꤹ롣

ĤΥե˶ͭå¾åƱꤹ뤳ȤϤǤʤ

.BR flock ()
ˤäƺåϡ
ץ󤵤줿եΥơ֥롦ȥȴϢդ롣
äơե롦ǥץʣ
.RB ( fork (2)

.BR dup (2)
ʤɤˤ) Ʊå򻲾Ȥ
Υե롦ǥץΤɤȤäƤ
ΥåѹǤ롣
ޤåβϡ
嵭ʣΥե롦ǥץΤ줫Ф
Ū
.B LOCK_UN
ؼ礫Υե롦ǥץ٤
Ĥ줿˹Ԥ롣

ץ
.BR open (2)
(⤷Ʊͤˡ) ȤäƱեФ
ʣΥǥץ硢
.BR flock ()
ϤʣΥǥץơΩΤΤȤư
Υե롦ǥץΰĤȤäƥեå褦
ݡΥå׵ϡƤӽФΥץΥե̤
ǥץͳǤǤꤷƤåˤäƵݤ礬롣

ĤΥץϡĤΥեФ (ͭå¾åΤ)
줫ΥåǤʤ
˥å줿եФ
.BR flock ()
ƤӽФȡ¸Υå򿷤å⡼ɤѹ뤳Ȥˤʤ롣

.BR flock ()
ˤ줿å
.BR execve (2)
¸롣

ͭå¾å⡢ե뤬ɤΥ⡼ɤǥץ󤵤줿
طʤŬѤ뤳ȤǤ롣
.SH ֤
ξ硢0 ֤롣顼ξϡ\-1 ֤졢
.I errno
Ŭڤͤꤵ롣
.SH 顼
.TP
.B EBADF
.I fd
ץ󤵤줿ե롦ǥץǤϤʤ
.TP
.B EINTR
åγԤäƤ֤ˡϥɥˤª줿ʥ

.BR flock ()
Ǥ줿
.TP
.B EINVAL
.I oepration
̵Ǥ롣
.TP
.B ENOLCK
å쥳ɤƤ뤿Υ꤬­Ƥ롣
.TP
.B EWOULDBLOCK
ꤷե뤬åƤꡢ
.B LOCK_NB
ե饰ꤵƤ롣
.SH 
4.4BSD
.RB ( flock ()
 4.2BSD Ǻǽо줷)
.BR fcntl (2)
ǼƤΤʤɤޤȡ
.BR flock ()
εǽϤۤȤɤ Unix ƥǼƤ롣
.SH 
.BR flock ()
 NFS ΥեΥå򤷤ʤ
.BR fcntl (2)
Ѥ뤳ȡˤꡢʬ˿С Linux ȡåǽ
ݡȤ NFS ФѤ뤳ȤˤꡢNFS ǥåǤ롣
.PP
kernel 2.0 ʹߤǤϡ
.BR flock ()
ϡGNU C 饤֥Ǥ
.BR fcntl (2)
ƤӽФƤΥߥ졼ǤϤʤ
켫ΤƥॳȤƼƤ롣
ˤä BSD Ǥưã:
.BR flock ()

.BR fcntl (2)
ŬѤåμ̤ˤߺѤʤʤꡢ
.BR flock ()
ǥåɥå򸡽Фʤʤ롣
.PP
.BR flock ()
ɥХꡦåŬѤ롣äơեŬڤʥ
ͿƤСץ
.BR flock ()
λѤ̵뤷ơեؤϤԤȤǤ롣
.PP
.BR flock ()

.BR fcntl (2)
 fork 줿ץ
.BR dup (2)
ǰäư򤹤롣
.BR flock ()

.BR fcntl (2)
ȤäƼƤ륷ƥǤϡ
.BR flock ()
ưϤΥޥ˥奢롦ڡ˵ܤƤΤȤϰ㤦
.PP
åѴ (ͭå¾åء⤷Ϥȿ) ȥߥå
Ԥ뤳ȤݾڤƤʤ: ¸Υåޤ졢줫鿷
åꤵ롣 2ĤΥƥåפδ֤ˡ¾ΥץνԤ
å׵᤬ǧ뤫⤷줺̤ȤѴ (block) ꡢ
.RB ( LOCK_NB
ꤵ줿ˤ) Ԥꤹ롣
(ϸ BSD ưǤꡢ¿¾μǤⵯ롣)
.\" ͥ 2.5.21 Ǿưѹ줿: åѴκ
.\" ΥåԤȤƤץǹͥȤʤ -- mtk
.SH Ϣ
.BR close (2),
.BR dup (2),
.BR execve (2),
.BR fcntl (2),
.BR fork (2),
.BR open (2),
.BR lockf (3)

ͥ륽
.IR Documentation/locks.txt ,
.I Documentation/mandatory.txt
⻲ȤΤȡ