[linuxjm/LDP_man-pages.git] / draft / man2 / write.2

.\" Hey Emacs! This file is -*- nroff -*- source.
.\"
.\" This manpage is Copyright (C) 1992 Drew Eckhardt;
.\"                               1993 Michael Haardt, Ian Jackson.
.\" and Copyright (C) 2007 Michael Kerrisk <mtk.manpages@gmail.com>
.\"
.\" 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.\" manual page may be incorrect or out-of-date.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 Sat Jul 24 13:35:59 1993 by Rik Faith <faith@cs.unc.edu>
.\" Modified Sun Nov 28 17:19:01 1993 by Rik Faith <faith@cs.unc.edu>
.\" Modified Sat Jan 13 12:58:08 1996 by Michael Haardt
.\"   <michael@cantor.informatik.rwth-aachen.de>
.\" Modified Sun Jul 21 18:59:33 1996 by Andries Brouwer <aeb@cwi.nl>
.\" 2001-12-13 added remark by Zack Weinberg
.\" 2007-06-18 mtk:
.\"     Added details about seekable files and file offset.
.\"     Noted that write() may write less than 'count' bytes, and
.\"     gave some examples of why this might occur.
.\"     Noted what happens if write() is interrupted by a signal.
.\"
.\" Japanese Version Copyright (c) 1997 HANATAKA Shinya
.\"         all rights reserved.
.\" Translated Tue Mar  4 00:18:20 JST 1997
.\"         by HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Updated & Modified Wed Jun 13 20:57:55 JST 2001
.\"         by Yuichi SATO <ysato@h4.dion.ne.jp>
.\" Updated Mon Jun 25 JST 2001 by Kentaro Shirakata <argrath@ub32.org>
.\" Updated Fri Dec 21 JST 2001 by Kentaro Shirakata <argrath@ub32.org>
.\" Updated 2002-09-24 by Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\" Updated 2005-10-14 by Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\" Updated 2007-05-01, Akihiro MOTOKI, LDP v2.46
.\" Updated 2007-09-01, Akihiro MOTOKI, LDP v2.64
.\" Updated 2008-04-13, Akihiro MOTOKI, LDP v3.20
.\"
.\"WORD:        descriptor              ¥Ç¥£¥¹¥¯¥ê¥×¥¿
.\"WORD:        buffer                  ¥Ð¥Ã¥Õ¥¡¡¼
.\"WORD:        file system             ¥Õ¥¡¥¤¥ë¡¦¥·¥¹¥Æ¥à
.\"WORD:        object                  ¥ª¥Ö¥¸¥§¥¯¥È
.\"WORD:        pipe                    ¥Ñ¥¤¥×
.\"WORD:        socket                  ¥½¥±¥Ã¥È
.\"WORD:        signal                  ¥·¥°¥Ê¥ë
.\"WORD:        catch                   Êá³Í(catch)
.\"WORD:        block                   Ää»ß(block)
.\"WORD:        interrupt               ³ä¤ê¹þ¤ß
.\"WORD:        nonblocking I/O         ÈóÄä»ß I/O
.\"WORD:        device                  ¥Ç¥Ð¥¤¥¹
.\"WORD:        low-level I/O           Äã¥ì¤Ù¥ë I/O
.\"
.TH WRITE 2 2010-08-29 "Linux" "Linux Programmer's Manual"
.\"O .SH NAME
.SH ̾Á°
.\"O write \- write to a file descriptor
write \- ¥Õ¥¡¥¤¥ë¡¦¥Ç¥£¥¹¥¯¥ê¥×¥¿ (file descriptor) ¤Ë½ñ¤­¹þ¤à
.\"O .SH SYNOPSIS
.SH ½ñ¼°
.B #include <unistd.h>
.sp
.BI "ssize_t write(int " fd ", const void *" buf ", size_t " count );
.\"O .SH DESCRIPTION
.SH ÀâÌÀ
.\"O .BR write ()
.\"O writes up to
.\"O .I count
.\"O bytes from the buffer pointed
.\"O .I buf
.\"O to the file referred to by the file descriptor
.\"O .IR fd .
.BR write ()
¤Ï¡¢
.I buf
¤¬»Ø¤¹¥Ð¥Ã¥Õ¥¡¤«¤é¡¢¥Õ¥¡¥¤¥ë¡¦¥Ç¥£¥¹¥¯¥ê¥×¥¿
.I fd
¤¬»²¾È¤¹¤ë¥Õ¥¡¥¤¥ë¤Ø¡¢ºÇÂç
.I count
¥Ð¥¤¥È¤ò½ñ¤­¹þ¤à¡£

.\"O The number of bytes written may be less than
.\"O .I count
.\"O if, for example,
.\"O there is insufficient space on the underlying physical medium, or the
.\"O .B RLIMIT_FSIZE
.\"O resource limit is encountered (see
.\"O .BR setrlimit (2)),
.\"O or the call was interrupted by a signal
.\"O handler after having written less than
.\"O .I count
.\"O bytes.
.\"O (See also
.\"O .BR pipe (7).)
½ñ¤­¹þ¤Þ¤ì¤ë¥Ð¥¤¥È¿ô¤Ï
.I count
¤è¤ê¤â¾®¤µ¤¯¤Ê¤ë¤³¤È¤¬¤¢¤ë¡£
Î㤨¤Ð¡¢½ñ¤­¹þ¤ßÂоݤÎʪÍý¥á¥Ç¥£¥¢¤Ë½½Ê¬¤ÊÎΰ褬¤Ê¤¤¾ì¹ç¡¢
¥ê¥½¡¼¥¹¾å¸Â
.B RLIMIT_FSIZE
¤Ë㤷¤¿¾ì¹ç
.RB ( setrlimit (2)
»²¾È)¡¢
.I count
¥Ð¥¤¥È̤Ëþ¤Î½ñ¤­¹þ¤ß¤¬¹Ô¤ï¤ì¤¿¸å¤Ç
¸Æ¤Ó½Ð¤·¤¬¥·¥°¥Ê¥ë¥Ï¥ó¥É¥é¤Ë¤è¤ê³ä¤ê¹þ¤Þ¤ì¤¿¾ì¹ç¡¢
¤Ê¤É¤Ç¤¢¤ë¡£
.RB ( pipe (7)
¤â»²¾È¤Î¤³¤È¡£)

.\"O For a seekable file (i.e., one to which
.\"O .BR lseek (2)
.\"O may be applied, for example, a regular file)
.\"O writing takes place at the current file offset,
.\"O and the file offset is incremented by
.\"O the number of bytes actually written.
.\"O If the file was
.\"O .BR open (2)ed
.\"O with
.\"O .BR O_APPEND ,
.\"O the file offset is first set to the end of the file before writing.
.\"O The adjustment of the file offset and the write operation
.\"O are performed as an atomic step.
seek ²Äǽ¤Ê¥Õ¥¡¥¤¥ë (¤Ä¤Þ¤ê
.BR lseek (2)
¤¬Å¬ÍѤǤ­¤ë¥Õ¥¡¥¤¥ë¡¢Î㤨¤ÐÄ̾ï¤Î¥Õ¥¡¥¤¥ë) ¤Ç¤Ï¡¢
½ñ¤­¹þ¤ß¤Ï¸½ºß¤Î¥Õ¥¡¥¤¥ë¡¦¥ª¥Õ¥»¥Ã¥È¤«¤é¹Ô¤ï¤ì¡¢
¥Õ¥¡¥¤¥ë¡¦¥ª¥Õ¥»¥Ã¥È¤Ï¼ÂºÝ¤Ë½ñ¤­¹þ¤ß¤¬¹Ô¤ï¤ì¤¿¥Ð¥¤¥È¿ôʬ
²Ã»»¤µ¤ì¤ë¡£¥Õ¥¡¥¤¥ë¤¬
.B O_APPEND
¤Ç
.BR open (2)
¤µ¤ì¤¿¾ì¹ç¡¢¥Õ¥¡¥¤¥ë¡¦¥ª¥Õ¥»¥Ã¥È¤Ï½ñ¤­¹þ¤ßÁ°¤Ë
¥Õ¥¡¥¤¥ë¤ÎËöÈø¤ËÀßÄꤵ¤ì¤ë¡£
¥Õ¥¡¥¤¥ë¡¦¥ª¥Õ¥»¥Ã¥È¤ÎÄ´À°¤È½ñ¤­¹þ¤ßÁàºî¤Ï¥¢¥È¥ß¥Ã¥¯¤Ê½èÍý¤È¤·¤Æ
¼Â¹Ô¤µ¤ì¤ë¡£

.\"O POSIX requires that a
.\"O .BR read (2)
.\"O which can be proved to occur after a
.\"O .BR write ()
.\"O has returned returns the new data.
.\"O Note that not all file systems are POSIX conforming.
POSIX ¤Ï
.BR write ()
¤¬¹Ô¤Ê¤ï¤ì¤¿¸å¤Ë¼Â¹Ô¤·¤¿
.BR read (2)
¤¬
¿·¤·¤¤¥Ç¡¼¥¿¤òÊÖ¤¹¤³¤È¤òÍ׵ᤷ¤Æ¤¤¤ë¡£
Á´¤Æ¤Î¥Õ¥¡¥¤¥ë¡¦¥·¥¹¥Æ¥à¤¬ POSIX ½àµò¤Ç¤Ï¤Ê¤¤ÅÀ¤ËÃí°Õ¤¹¤ë¤³¤È¡£
.\"O .SH "RETURN VALUE"
.SH ÊÖ¤êÃÍ
.\"O On success, the number of bytes written is returned (zero indicates
.\"O nothing was written).
.\"O On error, \-1 is returned, and \fIerrno\fP is set
.\"O appropriately.
À®¸ù¤·¤¿¾ì¹ç¡¢½ñ¤­¹þ¤Þ¤ì¤¿¥Ð¥¤¥È¿ô¤¬ÊÖ¤µ¤ì¤ë
(¥¼¥í¤Ï²¿¤â½ñ¤­¹þ¤Þ¤ì¤Ê¤«¤Ã¤¿¤³¤È¤ò¼¨¤¹)¡£
¥¨¥é¡¼¤Ê¤é¤Ð \-1 ¤¬ÊÖ¤µ¤ì¡¢\fIerrno\fP ¤¬Å¬ÀÚ¤ËÀßÄꤵ¤ì¤ë¡£

.\"O If \fIcount\fP is zero and
.\"O .I fd
.\"O refers to a regular file, then
.\"O .BR write ()
.\"O may return a failure status if one of the errors below is detected.
.\"O If no errors are detected,
.\"O 0 will be returned without causing any other effect.
.\"O If
.\"O \fIcount\fP is zero and
.\"O .I fd
.\"O refers to a file other than a regular file,
.\"O the results are not specified.
\fIcount\fP ¤¬ 0 ¤Ç¡¢
.I fd
¤¬Ä̾ï¤Î¥Õ¥¡¥¤¥ë (regular file) ¤ò»²¾È¤·¤Æ¤¤¤ë¾ì¹ç¡¢
.BR write ()
¤Ï¸å½Ò¤Î¥¨¥é¡¼¤Î¤¤¤º¤ì¤«¤ò¸¡½Ð¤·¤¿¾ì¹ç¡¢¼ºÇÔ¤òÊÖ¤¹¤³¤È¤¬¤¢¤ë¡£
¥¨¥é¡¼¤¬¸¡½Ð¤µ¤ì¤Ê¤«¤Ã¤¿¾ì¹ç¤Ï¡¢
0 ¤òÊÖ¤·¡¢Â¾¤Ë²¿¤Î±Æ¶Á¤âÍ¿¤¨¤Ê¤¤¡£
\fIcount\fP ¤¬ 0 ¤Ç¡¢
.I fd
¤¬Ä̾ï¤Î¥Õ¥¡¥¤¥ë°Ê³°¤Î¥Õ¥¡¥¤¥ë¤ò»²¾È¤·¤Æ¤¤¤ë¾ì¹ç¡¢
¤½¤Î·ë²Ì¤Ïµ¬Äꤵ¤ì¤Æ¤¤¤Ê¤¤¡£
.\"O .SH ERRORS
.SH ¥¨¥é¡¼
.TP
.B EAGAIN
.\"O The file descriptor
.\"O .I fd
.\"O refers to a file other than a socket and has been marked nonblocking
.\"O .RB ( O_NONBLOCK ),
.\"O and the write would block.
¥Õ¥¡¥¤¥ë¡¦¥Ç¥£¥¹¥¯¥ê¥×¥¿
.I fd
¤¬¥½¥±¥Ã¥È°Ê³°¤Î¥Õ¥¡¥¤¥ë¤ò»²¾È¤·¤Æ¤¤¤Æ¡¢
ÈóÄä»ß (nonblocking) ¥â¡¼¥É
.RB ( O_NONBLOCK )
¤ËÀßÄꤵ¤ì¤Æ¤ª¤ê¡¢½ñ¤­¹þ¤ß¤ò¹Ô¤¦¤ÈÄä»ß¤¹¤ë¾õ¶·¤Ë¤¢¤ë¡£
.TP
.\"O .BR EAGAIN " or " EWOULDBLOCK
.BR EAGAIN " ¤Þ¤¿¤Ï " EWOULDBLOCK
.\" Actually EAGAIN on Linux
.\"O The file descriptor
.\"O .I fd
.\"O refers to a socket and has been marked nonblocking
.\"O .RB ( O_NONBLOCK ),
.\"O and the write would block.
.\"O POSIX.1-2001 allows either error to be returned for this case,
.\"O and does not require these constants to have the same value,
.\"O so a portable application should check for both possibilities.
¥Õ¥¡¥¤¥ë¡¦¥Ç¥£¥¹¥¯¥ê¥×¥¿
.I fd
¤¬¥½¥±¥Ã¥È¤ò»²¾È¤·¤Æ¤¤¤Æ¡¢ÈóÄä»ß (nonblocking) ¥â¡¼¥É
.RB  ( O_NONBLOCK )
¤ËÀßÄꤵ¤ì¤Æ¤ª¤ê¡¢½ñ¤­¹þ¤ß¤ò¹Ô¤¦¤ÈÄä»ß¤¹¤ë¾õ¶·¤Ë¤¢¤ë¡£
POSIX.1-2001 ¤Ï¡¢¤³¤Î¾ì¹ç¤Ë¤É¤Á¤é¤Î¥¨¥é¡¼¤òÊÖ¤¹¤³¤È¤âǧ¤á¤Æ¤ª¤ê¡¢
¤³¤ì¤é 2 ¤Ä¤ÎÄê¿ô¤¬Æ±¤¸Ãͤò»ý¤Ä¤³¤È¤âµá¤á¤Æ¤¤¤Ê¤¤¡£
¤·¤¿¤¬¤Ã¤Æ¡¢°Ü¿¢À­¤¬É¬Íפʥ¢¥×¥ê¥±¡¼¥·¥ç¥ó¤Ç¤Ï¡¢Î¾Êý¤Î²ÄǽÀ­¤ò
³Îǧ¤¹¤Ù¤­¤Ç¤¢¤ë¡£
.TP
.B EBADF
.\"O .I fd
.\"O is not a valid file descriptor or is not open for writing.
.I fd
¤¬Í­¸ú¤Ê¥Õ¥¡¥¤¥ë¡¦¥Ç¥£¥¹¥¯¥ê¥×¥¿¤Ç¤Ê¤¤¤«½ñ¤­¹þ¤ß¤Î¤¿¤á¤Ë¥ª¡¼¥×¥ó
(open) ¤µ¤ì¤Æ¤¤¤Ê¤¤¡£
.TP
.B EDESTADDRREQ
.\"O .I fd
.\"O refers to a datagram socket for which a peer address has not been set using
.\"O .BR connect (2).
.I fd
¤¬¡¢
.BR connect (2)
¤ò»È¤Ã¤ÆÄÌ¿®Áê¼ê¤Î¥¢¥É¥ì¥¹¤¬ÀßÄꤵ¤ì¤Æ¤¤¤Ê¤¤¥Ç¡¼¥¿¥°¥é¥à¥½¥±¥Ã¥È¤ò
»²¾È¤·¤Æ¤¤¤ë¡£
.TP
.B EFAULT
.\"O .I buf
.\"O is outside your accessible address space.
.I buf
¤¬¥¢¥¯¥»¥¹²Äǽ¤Ê¥¢¥É¥ì¥¹¶õ´Ö (address space) ¤Î³°¤Ë¤¢¤ë¡£
.TP
.B EFBIG
.\"O An attempt was made to write a file that exceeds the implementation-defined
.\"O maximum file size or the process's file size limit,
.\"O or to write at a position past the maximum allowed offset.
¼ÂÁõÄêµÁ¤ÎºÇÂç¥Õ¥¡¥¤¥ë¥µ¥¤¥º¤Þ¤¿¤Ï¥×¥í¥»¥¹¤Î¥Õ¥¡¥¤¥ë¥µ¥¤¥ºÀ©¸Â¤ò
Ķ¤¨¤Æ¥Õ¥¡¥¤¥ë¤Ë½ñ¤­¹þ¤â¤¦¤È¤·¤¿¡£
¤Þ¤¿¤Ïµö²Ä¤µ¤ì¤¿¥ª¥Õ¥»¥Ã¥ÈÃͤ賦¤òĶ¤¨¤¿Àè¤Î°ÌÃÖ¤Ë
½ñ¤­¹þ¤â¤¦¤È¤·¤¿¡£
.TP
.B EINTR
.\"O The call was interrupted by a signal before any data was written; see
.\"O .BR signal (7).
²¿¤Î¥Ç¡¼¥¿¤â½ñ¤«¤Ê¤¤´Ö¤Ë¥·¥°¥Ê¥ë¤Ë¤è¤ê³ä¤ê¹þ¤Þ¤ì¤¿ (interrupt)¡£
.BR signal (7)
»²¾È¡£
.TP
.B EINVAL
.\"O .I fd
.\"O is attached to an object which is unsuitable for writing;
.\"O or the file was opened with the
.\"O .B O_DIRECT
.\"O flag, and either the address specified in
.\"O .IR buf ,
.\"O the value specified in
.\"O .IR count ,
.\"O or the current file offset is not suitably aligned.
.I fd
¤¬½ñ¤­¹þ¤ß¤¬ÉÔŬÀڤʥª¥Ö¥¸¥§¥¯¥È¤ò»²¾È¤·¤Æ¤¤¤ë¡£
¤â¤·¤¯¤Ï¡¢¥Õ¥¡¥¤¥ë¤¬
.B O_DIRECT
¥Õ¥é¥°¤ò»ØÄꤷ¤Æ¥ª¡¼¥×¥ó¤µ¤ì¤Æ¤¤¤ë¤¬¡¢
.I buf
¤Ë»ØÄꤵ¤ì¤¿¥¢¥É¥ì¥¹¡¢
.I count
¤Ë»ØÄꤵ¤ì¤¿ÃÍ¡¢
¸½ºß¤Î¥Õ¥¡¥¤¥ë¥ª¥Õ¥»¥Ã¥È¤Î¤¤¤º¤ì¤«¤Î
¥¢¥é¥¤¥ó¥á¥ó¥È¤¬ÉÔŬÀڤǤ¢¤ë¡£
.TP
.B EIO
.\"O A low-level I/O error occurred while modifying the inode.
inode ¤Î½¤ÀµÃæ¤ËÄã¥ì¤Ù¥ë (low-level) I/O ¥¨¥é¡¼¤¬È¯À¸¤·¤¿¡£
.TP
.B ENOSPC
.\"O The device containing the file referred to by
.\"O .I fd
.\"O has no room for the data.
.I fd
¤Ë¤è¤Ã¤Æ»²¾È¤µ¤ì¤ë¥Õ¥¡¥¤¥ë¤ò´Þ¤à¥Ç¥Ð¥¤¥¹ (device) ¤Ë½½Ê¬¤Ê¶õ¤­¤¬¤Ê¤¤¡£
.TP
.B EPIPE
.\"O .I fd
.\"O is connected to a pipe or socket whose reading end is closed.
.\"O When this happens the writing process will also receive a
.\"O .B SIGPIPE
.\"O signal.
.\"O (Thus, the write return value is seen only if the program
.\"O catches, blocks or ignores this signal.)
.I fd
¤¬¥Ñ¥¤¥× (pipe) ¤«¥½¥±¥Ã¥È (socket) ¤ËÀܳ¤µ¤ì¤Æ¤ª¤ê¡¢
¤½¤ÎÈ¿ÂЦ (Æɤ߹þ¤ß¦) ¤¬¥¯¥í¡¼¥º (close) ¤µ¤ì¤Æ¤¤¤ë¡£
¤³¤ì¤¬È¯À¸¤·¤¿¾ì¹ç¤Ë¤Ï¡¢½ñ¤­¹þ¤ß¤ò¹Ô¤Ê¤¦¥×¥í¥»¥¹¤Ï
.B SIGPIPE
¥·¥°¥Ê¥ë (signal)¤â¼õ¤±¤ë¡£
(¤·¤¿¤¬¤Ã¤Æ¡¢¥×¥í¥°¥é¥à¤¬¤³¤Î¥·¥°¥Ê¥ë¤òÊá³Í (catch)¡¢Ää»ß (block)¡¢Ìµ»ë (ignore)
¤·¤¿¾ì¹ç¤Î¤ß¡¢write ¤ÎÊÖ¤êÃͤò»²¾È¤Ç¤­¤ë¡£)
.PP
.\"O Other errors may occur, depending on the object connected to
.\"O .IR fd .
.I fd
¤ËÀܳ¤µ¤ì¤¿¥ª¥Ö¥¸¥§¥¯¥È¤Ë¤è¤Ã¤Æ¤Ï¡¢Â¾¤Î¥¨¥é¡¼¤¬µ¯¤³¤ë¤«¤â¤·¤ì¤Ê¤¤¡£
.\"O .SH "CONFORMING TO"
.SH ½àµò
SVr4, 4.3BSD, POSIX.1-2001.
.\"O .\" SVr4 documents additional error
.\"O .\" conditions EDEADLK, ENOLCK, ENOLNK, ENOSR, ENXIO, or ERANGE.
.\" SVr4 ¤Ë¤Ï¾¤Ë EDEADLK, ENOLCK, ENOLNK,
.\" ENOSR, ENXIO, ERANGE ¥¨¥é¡¼¤Ë¤Ä¤¤¤Æ¤Îµ­½Ò¤¬¤¢¤ë¡£

.\"O Under SVr4 a write may be interrupted and return
.\"O .B EINTR
.\"O at any point,
.\"O not just before any data is written.
SVr4 ¤Ç¤Ï write ¤¬³ä¤ê¹þ¤Þ¤ì¤ë¤È¡¢¥Ç¡¼¥¿¤¬½ñ¤­¹þ¤Þ¤ì¤ëľÁ°¤Ç¤Ï¤Ê¤¯¡¢
¤½¤Î»þÅÀ¤Ç
.B EINTR
¤¬Ê֤롣
.\"O .SH NOTES
.SH Ãí°Õ
.\"O A successful return from
.\"O .BR write ()
.\"O does not make any guarantee that data has been committed to disk.
.BR write ()
¤¬À®¸ù¤·¤ÆÊ֤äƤ­¤Æ¤â¡¢¥Ç¡¼¥¿¤¬¥Ç¥£¥¹¥¯¤Ëµ­Ï¿¤µ¤ì¤¿¤³¤È¤ò
Êݾڤ¹¤ë¤â¤Î¤Ç¤Ï¤Ê¤¤¡£
.\"O In fact, on some buggy implementations, it does not even guarantee
.\"O that space has successfully been reserved for the data.
¼ÂºÝ¡¢¥Ç¡¼¥¿¤Î¤¿¤á¤Î¥¹¥Ú¡¼¥¹¤¬³ÎÊݤµ¤ì¤¿¤³¤È¤¹¤éÊݾڤµ¤ì¤Ê¤¤¤È¤¤¤¦
¥Ð¥°¤Ã¤Ý¤¤¼ÂÁõ¤â¤¢¤ë¡£
.\"O The only way to be sure is to call
.\"O .BR fsync (2)
.\"O after you are done writing all your data.
¤³¤ì¤ò³Î¼Â¤Ë¤¹¤ëÍ£°ì¤ÎÊýË¡¤Ï¡¢
Á´¤Æ¤Î¥Ç¡¼¥¿¤ò write ¤·¤¿¸å¤Ë
.BR fsync (2)
¤ò¸Æ¤Ó½Ð¤¹¤³¤È¤Ç¤¢¤ë¡£

.\"O If a
.\"O .BR write ()
.\"O is interrupted by a signal handler before any bytes are written,
.\"O then the call fails with the error
.\"O .BR EINTR ;
.\"O if it is interrupted after at least one byte has been written,
.\"O the call succeeds, and returns the number of bytes written.
.BR write ()
¤¬ 1 ¥Ð¥¤¥È¤â½ñ¤­¹þ¤Þ¤Ê¤¤¤¦¤Á¤Ë¥·¥°¥Ê¥ë¥Ï¥ó¥É¥é¤Ë¤è¤ê³ä¤ê¹þ¤Þ¤ì¤¿¾ì¹ç¡¢
.BR write ()
¤Ï¥¨¥é¡¼
.B EINTR
¤Ç¼ºÇÔ¤¹¤ë¡£
1¥Ð¥¤¥È¤Ç¤â½ñ¤­¹þ¤ó¤À¸å¤Ç³ä¤ê¹þ¤Þ¤ì¤¿¾ì¹ç¤Ë¤Ï¡¢
.BR write ()
¤ÏÀ®¸ù¤·¡¢½ñ¤­¹þ¤ó¤À¥Ð¥¤¥È¿ô¤òÊÖ¤¹¡£
.\"O .SH "SEE ALSO"
.SH ´ØÏ¢¹àÌÜ
.BR close (2),
.BR fcntl (2),
.BR fsync (2),
.BR ioctl (2),
.BR lseek (2),
.BR open (2),
.BR pwrite (2),
.BR read (2),
.BR select (2),
.BR writev (2),
.BR fwrite (3)