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.\" This manpage is Copyright (C) 1992 Drew Eckhardt;
.\"                               1993 Michael Haardt, Ian Jackson.
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.\" Formatted or processed versions of this manual, if unaccompanied by
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.\" Modified Sat Jul 24 00:06:00 1993 by Rik Faith <faith@cs.unc.edu>
.\" Modified Wed Jan 17 16:02:32 1996 by Michael Haardt
.\"   <michael@cantor.informatik.rwth-aachen.de>
.\" Modified Thu Apr 11 19:26:35 1996 by Andries Brouwer <aeb@cwi.nl>
.\" Modified Sun Jul 21 18:59:33 1996 by Andries Brouwer <aeb@cwi.nl>
.\" Modified Fri Jan 31 16:47:33 1997 by Eric S. Raymond <esr@thyrsus.com>
.\" Modified Sat Jul 12 20:45:39 1997 by Michael Haardt
.\"   <michael@cantor.informatik.rwth-aachen.de>
.\"
.\" Japanese Version Copyright (c) 1997 HANATAKA Shinya
.\"         all rights reserved.
.\" Translated Sun Feb 23 20:01:28 JST 1997
.\"         by HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Modified Sun Sep 28 20:00:05 JST 1997
.\"         by HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\"
.\"WORD:	descriptor		ǥץ
.\"WORD:	buffer			Хåե
.\"WORD:	signal			ʥ
.\"WORD:	process group		ץ롼
.\"WORD:	backgraound		Хå
.\"WORD:	orphan			Ω
.\"WORD:	open			ץ
.\"WORD:	directory		ǥ쥯ȥ
.\"WORD:	object			֥
.\"
.TH READ 2 "July 12, 1997" "Linux 2.0.32" "Linux Programmer's Manual"
.SH ̾
read \- ե롦ǥץɤ߹
.SH 
.nf
.B #include <unistd.h>
.sp
.BI "ssize_t read(int " fd ", void *" buf ", size_t " count );
.fi
.SH 
.B read()
ϥե롦ǥץ(file descriptor)
.I fd

.I count
ХȤ
.IR buf
ǻϤޤХåեɤ߹⤦Ȥ롣
.PP
.I count
ʤС\fBread()\fP ϥ֤¾˲ⵯʤ
.I count
 SSIZE_MAX 礭С̤Ǥʤ
.PP
.SH ֤
硢ɤ߹Хȿ֤(ϥեν̣)
ե֤Ϥοʤ롣
ο׵ᤷ꾮äȤƤ⥨顼ǤϤʤ; 
㤨кˤϼºݤˤοʤ(եκǸ˶ᤤΤ
ʤѥ(pipe)ü(terminal)ɤ߹Ǥ뤫⤷ʤ)
\fBread()\fP ʥ(signal)ˤäƳޤ줿ˤϵ
롣
顼ξϡ\-1 ֤졢
.I errno
Ŭڤꤵ롣ξϥե֤ѹ뤫ɤ
Ǥ롣
.SH 顼
.TP
.B EINTR
Υǡɤ߹ޤʤ˥ʥ˳ޤ줿
.TP
.B EAGAIN 
.B O_NONBLOCK
Ѥ(Non-blocking) I/O 򤵤Ƥꡢ
˥ǡɤ߹߲ǽǤʤä
.TP
.B EIO
I/O 顼㤨ХץХåɡץ롼פǡ
椷Ƥ tty ɤߤ⤦ȤSIGTTIN ̵(ignore)ޤ
ػ(blocking)Ƥ䡢Υץ롼פΩ(orphan)
˵롣ޤǥơפɤǤ٥ I/O 顼
ȯˤⵯ롣
.TP
.B EISDIR
.I fd
ǥ쥯ȥ򻲾ȤƤ롣
.TP
.B EBADF
.I fd
ͭʥե롦ǥץǤʤɤ߹ߤΤ
ץ(open)Ƥʤ
.TP
.B EINVAL
.I fd
ɤ߹ߤŬƤʤ֥Ȥ򻲾ȤƤ롣
.TP
.B EFAULT
.I buf
ǽʥɥ쥹֤γˤ롣
.PP
.IR fd 
³Ƥ륪֥ȤˤäƤ¾Υ顼ⵯꤨ롣
POSIX Ǥϡ
餫Υǡɤ˳ߤä硢
.B read
(
.I errno
 EINTR ꤷ) \-1 ֤Ƥ褤
ɤ߹Хȿ֤Ƥ褤

.SH 
SVr4, SVID, AT&T, POSIX, X/OPEN, BSD 4.3
.SH 
NFS ˤơ̤Υǡɤ߹硢ǽλΤߤ˥ࡦ
פ졢³ǤϹʤ
ϥ饤¦°Υå󥰤ԤʤǤ롣
ʤʤС⤷Ƥ NFS 饤Ȥ atime()ι
С餺饤¦ǥåɤळȤ­ƤС
С¦Ǥ read ȯʤΤ atime ιϹԤʤʤ
UNIX Ǥϡ饤¦°Υå󥰤̵ˤ뤳Ȥǡ
뤳ȤǤ롣ۤȤɤξǤϤ³С
٤äѥեޥ󥹤㲼⤿餹
.SH Ϣ
.BR close (2),
.BR fcntl (2),
.BR ioctl (2),
.BR lseek (2),
.BR readdir (2),
.BR readlink (2),
.BR select (2),
.BR write (2),
.BR fread (3)