.\" Copyright (c) 1983, 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"	This product includes software developed by the University of
.\"	California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" Modified 1993-07-24 by Rik Faith <faith@cs.unc.edu>
.\" Modified 1996-10-22 by Eric S. Raymond <esr@thyrsus.com>
.\" Modified Oct 1998 by Andi Kleen
.\" Modified Oct 2003 by aeb
.\" Modified 2004-07-01 by mtk
.\"
.\" Japanese Version Copyright (c) 1996 HANATAKA Shinya all rights reserved.
.\" Translated 1997-02-23, HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Updated 1999-08-15, HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Updated 2000-01-13, Kentaro Shirakata <argrath@ub32.org>
.\" Updated 2001-01-30, Kentaro Shirakata <argrath@ub32.org>
.\" Updated 2005-03-14, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\" Updated 2005-12-26, Akihiro MOTOKI
.\" Updated 2006-04-15, Akihiro MOTOKI, Catch up to LDP v2.29
.\"
.\"WORD:	socket			å
.\"WORD:	message			å
.\"WORD:	protocol		ץȥ
.\"WORD:	non-blocking I/O	 I/O
.\"WORD:	block			(block)
.\"WORD:	out-of-band		Ӱ賰
.\"WORD:	descriptor		ǥץ
.\"WORD:	parameter		ѥ᡼
.\"WORD:	queue			塼
.\"WORD:	buffer			Хåե
.\"WORD:	routing			롼ƥ
.\"WORD:	congestion		
.\"
.TH SEND 2 2004-07-01 "Linux 2.6.7" "Linux Programmer's Manual"
.SH ̾
send, sendto, sendmsg \- åȤإå
.SH 
.B #include <sys/types.h>
.br
.B #include <sys/socket.h>
.sp
.BI "ssize_t send(int " s ", const void *" buf ", size_t " len ,
.BI "int " flags );
.br
.BI "ssize_t sendto(int " s ", const void *" buf ", size_t " len ,
.BI "int " flags ", const struct sockaddr *" to ", socklen_t " tolen );
.br
.BI "ssize_t sendmsg(int " s ", const struct msghdr *" msg ,
.BI "int " flags );
.SH 
ƥॳ
.BR send (),
.BR sendto (),
.BR sendmsg ()
ϡ⤦ΥåȤإåžΤ˻Ѥ롣
.PP
.BR send ()
ϡåȤ
.I "³줿 (connected)"
֤ˤˤΤ߻ѤǤ
(Ĥޤꡢɤ뤫ϴΤǤ)
.BR send ()

.BR write ()
ΰ㤤ϡ
.I flags
뤫ɤǤ롣

.I flags
 0 ξ硢
.BR send ()

.BR write ()
Ǥ롣
ޤ
.RI send( s , buf , len , flags )

.RI sendto( s , buf , len , flags ,NULL,0)
Ǥ롣
.PP

.I s
ϡǡѥåȤΥե롦ǥץǤ롣
.PP
.BR sendto ()
ϡ³ (connection-mode) Υå (SOCK_STREAM, SOCK_SEQPACKET) 
Ѥ줿硢
.I to

.I tolen
̵뤵 (ơΰ NULL  0 Ǥʤ EISCONN 顼֤)
ޤåȤºݤˤ³Ƥʤäˤ ENOTCONN 顼֤롣
³ΥåȰʳǻѤ줿ϡ³Υɥ쥹
.I to
Ϳ졢Υ
.I tolen
ǻꤵ롣
.BR sendmsg ()
Ǥϡ³Υɥ쥹
.I msg.msg_name
Ϳ졢Υ
.I msg.msg_namelen
ǻꤵ롣
.PP
.BR send ()

.BR sendto ()
Ǥϡå
.I buf
˳ǼƤꡢĹ
.I len
ǤȲᤵ롣
.BR sendmsg ()
Ǥϡå

.I msg.msg_iov
γǤؤ֤˳ǼƤ롣
.BR sendmsg ()
Ǥϡǡ (ȤƤФ) 뤳ȤǤ롣
.PP
åĹĹ᤮뤿ˡΥåȤѤץȥǤϡ
å򥽥åȤϤ줿ޤޤη뤳ȤǤʤ硢
.B EMSGSIZE
顼֤졢Υåžʤ
.PP
.BR send ()
ǤϡμԤΤŪ˹Ԥ롣
¦ǥ顼Ф줿ϡ֤ \-1 ȤΤ롣
.PP
ååȤХåե뤳ȤǤʤ硢
.BR send ()
̾ (block)  (åȤ (non-blocking) I/O ⡼
Ǥʤ)ߥ⡼ɤξˤ
.B EAGAIN
֤ĥǡ򤵤Ǥ褦ˤʤ뤫Τ뤿ˡ
.BR select (2)
Ѥ뤳ȤǤ롣
.PP
.I flags
ѥ᡼ϡʲΥե饰 (0 İʾ) ӥåñ̤¤
ȤäΤꤹ롣
.\" FIXME? MSG_PROXY ˤĤƵܤ뤳
.\" (MSG_PROXY  2.3.15 Ǥʤʤä)
.TP
.BR MSG_CONFIRM " (Linux 2.3 ʹߤΤ)"
ž˿ŸäĤޤ¦αȤؤ
Τ餻롣ؤΤʤäˤϡ̾ɤ
(˥㥹 ARP Ȥʤɤˡ) ˵ (neighbour) κƸԤ
.B SOCK_DGRAM

.B SOCK_RAW
ΥåȤФƤΤͭǡߤΤȤ IPv4  IPv6 Τ߼Ƥ롣
ܤ
.BR arp (7)
ȤΤȡ
.TP
.B MSG_DONTROUTE
ѥåȤФΤ˥ȥѤ
ľ³ƤͥåȥΥۥȤ롣
̾Υե饰Ͽ (diagnostic) 롼ƥ󥰡ץ
äƤΤ߻Ѥ롣Υե饰ϡϩ椬Ԥץȥեߥ꡼
ФƤΤƤ롣ѥåȥåȤˤƤʤ
.TP
.B MSG_DONTWAIT
 (non-blocking) ͭˤ롣ߤ褦ʾˤ
.B EAGAIN
֤褦ˤ
.RB ( fcntl (2)

.B F_SETFL

.B O_NONBLOCK
ꤹ뤳ȤˤäƤͭˤǤ)
.TP
.B MSG_EOR
쥳ɤνλؼ
.RB ( SOCK_SEQPACKET
Τ褦ˤγǰбƤ륽åȼ̤ΤȤͭ)
.TP
.BR MSG_MORE " (Linux 2.4.4 ʹ)"
ƤӽФˤǡ뤳Ȥ򼨤
Υե饰 TCP åȤȤȤ˻Ѥ졢
TCP_CORK åȥץƱ̤
.RB ( tcp (7)
򻲾) TCP_CORK Ȥΰ㤤ϡΥե饰ȤȸƤӽФñ̤
εǽͭˤǤǤ롣
Linux 2.6 ʹߤǤϡΥե饰 UDP åȤǤ⥵ݡȤƤꡢ
Υե饰դ줿ƤΥǡĤΥǡˤޤȤ
뤳Ȥ򡢥ͥΤ餻롣ޤȤ줿ǡϡ
Υե饰ꤻˤΥƥॳ뤬¹Ԥ줿ݤ˽
.RB ( udp (7)
˵ܤƤ륽åȥץ
.B UDP_CORK
⻲)
.TP
.B MSG_NOSIGNAL
ȥ꡼ظΥåȤ¦³Ǥˡ顼Ȥ
.B SIGPIPE
ʤ褦׵᤹롣ξǤ
.B EPIPE
֤롣
.TP
.B MSG_OOB
.I "Ӱ賰 (out-of-band)"
ǡ򥵥ݡȤ륽å (㤨
.BR SOCK_STREAM )

.I Ӱ賰
ǡ롣̥ץȥ
.I Ӱ賰
ǡ򥵥ݡȤƤɬפ롣
.PP
.I msghdr
¤ΤƤϰʲ̤ꡣ
ƥեɤΤʵҤˤĤƤ
.BR recv (2)
Ȱʲ򻲾Ȥ뤳ȡ
.in +0.25i
.nf

struct msghdr {
    void         *msg_name;       /* ɲäΥɥ쥹 */
    socklen_t     msg_namelen;    /* ɥ쥹Υ */
    struct iovec *msg_iov;        /* scatter/gather  */
    size_t        msg_iovlen;     /* msg_iov ǿ */
    void         *msg_control;    /* ǡ() */
    socklen_t     msg_controllen; /* ǡХåեĹ */
    int           msg_flags;      /* åΥե饰 */
};
.fi
.in -0.25i
.PP
.I msg_control

.I msg_controllen
СѤ뤳ȤǤ롣
ͥ뤬ǤХåեΥåȤκĹϡ
sysctl ѥ᡼
.B net.core.optmem_max
ͤ¤Ƥ롣
.BR socket (7)
򻲾ȡ
.\" Still to be documented:
.\"  Send file descriptors and user credentials using the
.\"  msg_control* fields.
.\"  The flags returned in msg_flags.
.SH ֤
硢Υƥॳ줿Хȿ֤
顼ξ硢 \-1 ֤
.I errno
Ŭڤˤ롣
.SH 顼
ϥåؤȯŪʥ顼Ǥ롣ʳˡؤ
ץȥ롦⥸塼줿顼֤뤫⤷ʤ
ˤĤƤϡ줾Υޥ˥奢򻲾Ȥ뤳ȡ
.TP
.B EACCES
(Unix ɥᥤ󥽥åȤϥѥ̾Ǽ̤롣)
åȡեؤν񤭹ߵĤʤäѥ̾
ãޤǤΥǥ쥯ȥΤ줫Ф븡Ĥʤä
.RB ( path_resolution (2)
⻲ȤΤ)
.TP
.BR EAGAIN " ޤ " EWOULDBLOCK
åȤߤꤵƤꡢ
׵ᤵ줿ߤ
.TP
.B EBADF
̵ʥǥץꤵ줿
.TP
.B ECONNRESET
³³ˤꥻåȤ줿
.TP
.B EDESTADDRREQ
åȤ³ (connection-mode) ǤϤʤ
Υɥ쥹ꤵƤʤ
.TP
.B EFAULT
桼֤Ȥʥɥ쥹ѥ᡼Ȥƻꤵ줿
.TP
.B EINTR
ǡˡʥ뤬ȯ
.TP
.B EINVAL
ʰϤ줿
.TP
.B EISCONN
³åȤ³Ǥ˳ΩƤԤꤵƤ
(ߤΤȤξǤϡΥ顼֤뤫
Ԥλ̵꤬뤵뤫Τ줫Ȥʤ)
.TP
.B EMSGSIZE
Υåȼ
.\" (㤨 SOCK_DGRAM)
ǤϥåȤϤ줿ޤޤηǥåɬפ뤬
å礭᤮뤿뤳ȤǤʤ
.TP
.B ENOBUFS
ͥåȥ󥿡եνϥ塼դǤ롣
ŪˤϡŪ (congestion) Τ˥󥿡ե
ߤƤ뤳Ȥ̣롣
(̾Linux ǤϤΤ褦ʤȤϵʤǥХΥ塼
СեˤϥѥåȤۤäƼΤƤ)
.TP
.B ENOMEM
꤬­ʤ
.TP
.B ENOTCONN
åȤ³Ƥ餺³ꤵƤʤ
.TP
.B ENOTSOCK

.I s
åȤǤʤ
.TP
.B EOPNOTSUPP

.I flags
ΤĤΥӥåȤΥåȼ̤ǤŬڤʤΤǤ롣
.TP
.B EPIPE
³ظΥåȤǥ¦ĤƤ롣
ξ硢
.B MSG_NOSIGNAL
ꤵƤʤСץˤ
.B SIGPIPE
Ʊ롣
.SH 
4.4BSD, SVr4, POSIX.1-2001.
(δؿ 4.2BSD Ǻǽо줷)

POSIX.1-2001 ˤϡ
.B MSG_OOB

.B MSG_EOR
ե饰ܤƤ롣
.B MSG_CONFIRM
ե饰 Linux ǤγĥǤ롣
.SH 
嵭Υץȥפ Single Unix Specification ˽äƤ롣
glibc2 ƱͤǤ롣
.I flags
 4.x BSD Ǥ int Ǥꡢlibc4  libc5 Ǥ unsigned int Ǥ롣
.I len
 4.x BSD  libc4 Ǥ int Ǥꡢlibc5 Ǥ `size_t' Ǥ롣
.I tolen
 4.x BSD  libc4  libc5 Ǥ `int' Ǥ롣
.BR accept (2)
⻲Ȥ뤳ȡ

POSIX.1-2001 Ǥϡ¤
.I msghdr
Υե
.I msg_controllen

.I socklen_t
Ǥ٤ȤƤ뤬
ߤ glibc (glibc 2.4) Ǥ
.I size_t
Ǥ롣
.\" glibc bug raised 12 Mar 2006
.\" http://sourceware.org/bugzilla/show_bug.cgi?id=2448
.\" The problem is an underlying kernel issue: the size of the
.\" __kernel_size_t type used to type this field varies
.\" across architectures, but socklen_t is always 32 bits.
.SH Х
Linux  ENOTCONN ֤ EPIPE ֤Ȥ롣
.SH Ϣ
.BR fcntl (2),
.BR getsockopt (2),
.BR recv (2),
.BR select (2),
.BR sendfile (2),
.BR shutdown (2),
.BR socket (2),
.BR write (2),
.BR cmsg (3),
.BR ip (7),
.BR socket (7),
.BR tcp (7),
.BR udp (7)