233 lines
6.2 KiB
Groff
233 lines
6.2 KiB
Groff
.\" Copyright (c) 1980, 1991, 1993
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.\" The Regents of the University of California. All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\" 3. All advertising materials mentioning features or use of this software
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.\" must display the following acknowledgement:
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.\" This product includes software developed by the University of
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.\" California, Berkeley and its contributors.
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.\" 4. Neither the name of the University nor the names of its contributors
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.\" may be used to endorse or promote products derived from this software
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.\" without specific prior written permission.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.\" @(#)read.2 8.4 (Berkeley) 2/26/94
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.\" %FreeBSD: src/lib/libc/sys/read.2,v 1.25.2.1 2004/11/13 11:55:41 yar Exp %
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.\"
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.\" $FreeBSD$
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.Dd October 16, 2004
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.Dt READ 2
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.Os
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.Sh ̾¾Î
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.Nm read ,
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.Nm readv ,
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.Nm pread
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.Nd ÆþÎϤòÆɤ߼è¤ë
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.Sh ¥é¥¤¥Ö¥é¥ê
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.Lb libc
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.Sh ½ñ¼°
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.In sys/types.h
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.In sys/uio.h
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.In unistd.h
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.Ft ssize_t
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.Fn read "int d" "void *buf" "size_t nbytes"
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.Ft ssize_t
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.Fn readv "int d" "const struct iovec *iov" "int iovcnt"
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.Ft ssize_t
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.Fn pread "int d" "void *buf" "size_t nbytes" "off_t offset"
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.Sh ²òÀâ
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.Fn read
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¥·¥¹¥Æ¥à¥³¡¼¥ë¤Ï¡¢µ½Ò»Ò
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.Fa d
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¤Ç»²¾È¤µ¤ì¤¿¥ª¥Ö¥¸¥§¥¯¥È¤«¤é
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.Fa buf
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¤¬»Ø¤¹¥Ð¥Ã¥Õ¥¡¤Ø
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.Fa nbytes
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.Fn readv
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.Fa iov
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: iov[0], iov[1], ..., iov[iovcnt\|\-\|1]
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¤Î¥á¥ó¥Ð¤Ç»ØÄꤵ¤ì¤ë
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.Pp
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¤ËÂФ¹¤ë
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¹½Â¤ÂΤϼ¡¤Î¤è¤¦¤ËÄêµÁ¤µ¤ì¤Þ¤¹:
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.Pp
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.Bd -literal -offset indent -compact
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struct iovec {
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void *iov_base; /* ¥Ù¡¼¥¹¥¢¥É¥ì¥¹ */
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size_t iov_len; /* Ťµ */
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};
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.Ed
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.Pf ( Xr lseek 2
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.Fa buf
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.It Bq Er EIO
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.It Bq Er EOVERFLOW
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¤¬ 0 ¤è¤ê¤âÂ礤¯¡¢
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¤Ï¼¡¤Î¥¨¥é¡¼¤Î¤¦¤Á¤Î 1 ¤Ä¤òÊÖ¤¹¤³¤È¤¬¤¢¤ê¤Þ¤¹:
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.Bl -tag -width Er
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.It Bq Er EINVAL
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.Fa iovcnt
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°ú¿ô¤¬ 0 °Ê²¼¤Ç¤¢¤ë¤«¡¢¤Þ¤¿¤Ï
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.Dv IOV_MAX
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.Fa iov
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.Fa iov
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.Fn pread
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.Fa offset
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.Sh ´ØÏ¢¹àÌÜ
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.Xr dup 2 ,
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.Xr fcntl 2 ,
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.Xr getdirentries 2 ,
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.Xr open 2 ,
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.Xr pipe 2 ,
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.Xr select 2 ,
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.Xr socket 2 ,
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.Xr socketpair 2 ,
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.Xr fread 3 ,
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.Xr readdir 3
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