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.\" Japanese Version Copyright (c) 2005 Akihiro MOTOKI all rights reserved.
.\" Translated 2005-12-26, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\"
.TH PIPE 7 2005-12-08 "Linux" "Linux Programmer's Manual"
.SH ̾
pipe \- ѥפ FIFO γ
.SH 
ѥפ FIFO (̾դѥפȤ⤤) ϡ
ñΥץ̿ͥ󶡤롣
ѥפˤϡɤ߽Ф¦פȡֽ񤭹¦פ롣
ѥפν񤭹¦ǽ񤭹ޤ줿ǡϡ
ѥפɤ߽Ф¦ɤ߽ФȤǤ롣

ѥפˤ
.BR pipe (2)
Ѥ롣
.BR pipe (2)
Ͽѥפե롦ǥץ֤
ǥץΤϥѥפɤ߽Ф¦򡢤⤦
񤭹¦򻲾ȤƤ롣
ѥפϴϢץ֤̿Τ˻ѤǤ롣

.BR pipe (2)
򻲾ȡ

FIFO (First In First Out ξά) ϥե륷ƥǤ̾
.BR open (2)
ȤäƥץǤ
.RB ( mkfifo (3)
Ȥäƺ)
ɤʥץǤ⡢եΥĤ FIFO 򥪡ץ󤹤
ȤǤ롣
ɤ߽Ф¦򥪡ץ󤹤ˤ
.B O_RDONLY
ե饰Ѥ񤭹¦򥪡ץ󤹤ˤ
.B O_WRONLY
ե饰Ѥ롣ܺ٤
.BR fifo (7)
򻲾ȡ
ա
FIFO ϥե륷ƥΥѥ̾Ĥ
FIFO ФϤԤäƤ⡢(ե륷ƥब¸ߤǥХ
äȤƤ) ΥǥХФȯʤ
.SS "ѥפ FIFO Ф"
ѥפ FIFO ΰ㤤Ϻ䥪ץˡǤ롣
λϡѥפ FIFO ФϤ
ƱȤߤǹԤ롣

ץΥѥפɤ߽ФԤȤ硢
.BR read (2)
ϥǡɤ߽Фǽˤʤޤߤ롣
ץե֤Υѥפ˽񤭹ߤԤȤ硢
.BR write (2)
Ͻ񤭹ߤλΤ˽ʬ̤Υѥפɤ߽Ф
Ԥޤߤ롣
 (non-blocking) I/O ȤȤǤ롣
 I/O Ȥˤϡ
.BR fcntl (2)
.B F_SETFL
Ȥäơ
.B O_NONBLOCK
ץե֥ե饰ͭˤ롣

ѥפˤ󶡤̿ͥϡ֥Хȥȥ꡼פǤꡢ
åγǰϤʤ

ѥפν񤭹¦򻲾ȤƤե롦ǥץ
٤ƥ줿ǡΥѥפ
.BR read (2)
ԤȤ硢
end-of-file (ե) 
.RB ( read (2)
 0 ֤)
ѥפɤ߽Ф¦򻲾ȤƤե롦ǥץ
٤ƥ줿ǡ
.BR write (2)
ԤȡƤӽФץ
.B SIGPIPE
ʥ뤬롣
ƤӽФץΥʥ̵뤷ƤȤˤϡ
.BR write (2)
ϥ顼
.B EPIPE
ǼԤ롣
.BR pipe (2)

.BR fork (2)
Ѥ륢ץꥱǤϡ
.BR close (2)
Ŭڤ˻Ȥäɬפʥե롦ǥץʣ
٤Ǥ롣뤳Ȥǡɬפʻ˳μ¤
end-of-file 
.BR SIGPIPE / EPIPE
褦ˤʤ롣

ѥפˤ
.BR lseek (2)
ԤȤϤǤʤ
.SS ѥפ
ѥפ̤ˤϾ¤롣
ѥפեξ硢
.BR write (2)
ߤ꼺Ԥꤹ롣ɤˤʤ뤫
.B O_NONBLOCK
ե饰åȤƤ뤫ɤ˰¸ ()
ˤꡢѥפ̤ξ¤ϰۤʤ롣
ץꥱ̤ˤ٤ǤϤʤ
񤭹¦Υץߤޤޤˤʤʤ褦
ɤ߽Ф¦ΥץϥǡѲǽˤʤäǤ
ɤ߽ФԤ褦ˡץꥱ߷פ٤Ǥ롣

С 2.6.11  Linux Ǥϥѥפ̤ϥƥΥڡ
ƱǤä (㤨 i386 Ǥ 4096 Х)
Linux 2.6.11 ʹߤǤϡѥפ̤ 65536 ХȤǤ롣
.SS PIPE_BUF
POSIX.1-2001 Ǥϡ
.B PIPE_BUF
ХȰʲ
.BR write (2)
 atomic ˹Ԥ뤳ȡĤޤѥפؤνϥǡν񤭹ߤ
Ϣ³󥹤ȤƹԤ뤳ȤɬܤȤƤ (MUST)
.B PIPE_BUF
ХȤ¿Υǡ񤭹߾ atomic ȤϤʤʤ
Ĥޤѥפؤ¾Υץˤǡν񤭹ߤ֤
ǽ롣
POSIX.1-2001 λͤǤϡ
.B PIPE_BUF
ϺǾǤ 512 ХȤǤ뤳Ȥ׵ᤵƤ
(Linux Ǥ
.B PIPE_BUF
 4096 ХȤǤ)
Τưϡե롦ǥץ non-blocking
.RB ( O_NONBLOCK )
ɤѥפؤν񤭹ߤʣԤ뤫ɤ
񤭹ߤԤХȿ
.I n
ˤꤵ롣
.TP
\fBO_NONBLOCK\fP ̵, \fIn\fP <= \fBPIPE_BUF\fP
.I n
Хν񤭹ߤ atomic ˹Ԥ롣
.I n
Хʬ򤹤˽񤭹;Ϥʤ
.BR write (2)
 (block) 뤳Ȥ롣
.TP
\fBO_NONBLOCK\fP ͭ, \fIn\fP <= \fBPIPE_BUF\fP
ѥפ
.I n
ХȤ񤭹;Ϥϡ
.I n
Х˽񤭹ޤ롣
;Ϥʤϡ
.BR write (2)
ϼԤ
.I errno

.B EAGAIN
åȤ롣
.TP
\fBO_NONBLOCK\fP ̵, \fIn\fP > \fBPIPE_BUF\fP
񤭹ߤ atomic ȤϤʤʤ
.BR write (2)
Ϥ줿ǡδ֤ˡ¾Υץˤ
.BR write (2)
줿ǡ뤳Ȥ롣
.BR write (2)

.I n
ХȤν񤭹ߤλޤߤ롣
.TP
\fBO_NONBLOCK\fP ͭ, \fIn\fP > \fBPIPE_BUF\fP
ѥפեξ硢
.BR write (2)
ϼԤ
.I errno

.B EAGAIN
åȤ롣
ʳξ硢1 ХȰʾ
.I n
ХȰʲΥǡ񤭹ޤ
(Ĥޤְʬ񤭹ޤ׾⤢)
ƤӽФ
.BR write (2)
֤ͤ򻲾Ȥºݤ˲ХȽ񤭹ޤ줿Τǧ٤Ǥ롣
ޤ񤭹ߤǡ⡢¾Υץ񤭹ǡ
֤뤳Ȥ롣
.SS ץե֥ե饰
ץե֥ե饰Τѥפ FIFO ФựĤΤ
.B O_NONBLOCK

.B O_ASYNC
Ǥ롣

ѥפɤ߽Ф¦
.B O_ASYNC
ե饰򥻥åȤȡѥפ˿Ϥȥʥ (ǥեȤǤ
.BR SIGIO )
 (ܺ٤
.BR fcntl (2)
򻲾)
Linux Ǥϡ
ѥפ FIFO Ф
.B O_ASYNC
ϥͥ 2.6 ʹߤǤΤߥݡȤƤ롣
.SS ܿ˴ؤ
ĤΥƥ (Linux ǤϤʤ) ǤϡѥפǤ롢
Ĥޤѥפξü֤ǥǡξ뤳ȤǤ롣
POSIX.1-2001 Ǥϡѥפϰ̿бƤФ褤
ܿθץꥱǤϡѥפλȤߤ
ˤ٤ǤϤʤ
.SH Ϣ
.BR dup (2),
.BR fcntl (2),
.BR open (2),
.BR pipe (2),
.BR poll (2),
.BR select (2),
.BR socketpair (2),
.BR stat (2),
.BR mkfifo (3),
.BR epoll (7),
.BR fifo (7)