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+.\" Copyright (C) 2011 by Andi Kleen <andi@firstfloor.org>
+.\" and Copyright (c) 2011 by Michael Kerrisk <mtk.manpages@gmail.com>
+.\"
+.\" Permission is granted to make and distribute verbatim copies of this
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+.\" preserved on all copies.
+.\"
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+.\" entire resulting derived work is distributed under the terms of a
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+.\" professionally.
+.\"
+.\" Formatted or processed versions of this manual, if unaccompanied by
+.\" the source, must acknowledge the copyright and authors of this work.
+.\"
+.\" FIXME: This page could be improved with an example program.
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+.\"*******************************************************************
+.\"
+.\" This file was generated with po4a. Translate the source file.
+.\"
+.\"*******************************************************************
+.TH RECVMMSG 2 2011\-10\-04 Linux "Linux Programmer's Manual"
+.SH 名前
+recvmmsg \- receive multiple messages on a socket
+.SH 書式
+.nf
+\fB#define _GNU_SOURCE\fP
+\fB#include <sys/socket.h>\fP
+
+\fBint recvmmsg(int \fP\fIsockfd\fP\fB, struct mmsghdr *\fP\fImsgvec\fP\fB, unsigned int \fP\fIvlen\fP\fB,\fP
+.br
+\fB unsigned int \fP\fIflags\fP\fB, struct timespec *\fP\fItimeout\fP\fB);\fP
+.fi
+.SH 説明
+The \fBrecvmmsg\fP() system call is an extension of \fBrecvmsg\fP(2) that allows
+the caller to receive multiple messages from a socket using a single system
+call. (This has performance benefits for some applications.) A further
+extension over \fBrecvmsg\fP(2) is support for a timeout on the receive
+operation.
+
+The \fIsockfd\fP argument is the file descriptor of the socket to receive data
+from.
+
+The \fImsgvec\fP argument is a pointer to an array of \fImmsghdr\fP structures.
+The size of this array is specified in \fIvlen\fP.
+
+The \fImmsghdr\fP structure is defined in \fI<sys/socket.h>\fP as:
+
+.in +4n
+.nf
+struct mmsghdr {
+ struct msghdr msg_hdr; /* Message header */
+ unsigned int msg_len; /* Number of received bytes for header */
+};
+.fi
+.in
+.PP
+The \fImsg_hdr\fP field is a \fImsghdr\fP structure, as described in
+\fBrecvmsg\fP(2). The \fImsg_len\fP field is the number of bytes returned for the
+message in the entry. This field has the same value as the return value of
+a single \fBrecvmsg\fP(2) on the header.
+
+The \fIflags\fP argument contains flags ORed together. The flags are the same
+as documented for \fBrecvmsg\fP(2), with the following addition:
+.TP
+\fBMSG_WAITFORONE\fP
+Turns on \fBMSG_DONTWAIT\fP after the first message has been received.
+.PP
+The \fItimeout\fP argument points to a \fIstruct timespec\fP (see
+\fBclock_gettime\fP(2)) defining a timeout (seconds plus nanoseconds) for the
+receive operation. If \fItimeout\fP is \fINULL\fP then the operation blocks
+indefinitely.
+
+A blocking \fBrecvmmsg\fP() call blocks until \fIvlen\fP messages have been
+received or until the timeout expires. A nonblocking call reads as many
+messages as are available (up to the limit specified by \fIvlen\fP) and
+returns immediately.
+
+On return from \fBrecvmmsg\fP(), successive elements of \fImsgvec\fP are updated
+to contain information about each received message: \fImsg_len\fP contains the
+size of the received message; the subfields of \fImsg_hdr\fP are updated as
+described in \fBrecvmsg\fP(2). The return value of the call indicates the
+number of elements of \fImsgvec\fP that have been updated.
+.SH 返り値
+On success, \fBrecvmmsg\fP() returns the number of messages received in
+\fImsgvec\fP; on error, \-1 is returned, and \fIerrno\fP is set to indicate the
+error.
+.SH エラー
+Errors are as for \fBrecvmsg\fP(2). In addition, the following error can
+occur:
+.TP
+\fBEINVAL\fP
+\fItimeout\fP is invalid.
+.SH バージョン
+The \fBrecvmmsg\fP() system call was added in Linux 2.6.32. Support in glibc
+was added in version 2.12.
+.SH 準拠
+\fBrecvmmsg\fP() is Linux\-specific.
+.SH 関連項目
+\fBclock_gettime\fP(2), \fBrecvmsg\fP(2), \fBsendmmsg\fP(2), \fBsendmsg\fP(2),
+\fBsocket\fP(2), \fBsocket\fP(7)
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