2004-11-03 13:51:07 +00:00
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.\" Copyright (c) 1983, 1990, 1991 The Regents of the University of California.
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.\" All rights reserved.
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.\"
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accept.2, bind.2, connect.2, getpeername.2, getpriority.2, getsockname.2, getsockopt.2, ioctl.2, killpg.2, listen.2, lseek.2, readlink.2, recv.2, send.2, setpgid.2, setreuid.2, shutdown.2, socket.2, socketpair.2, syscall.2, truncate.2, alloca.3, btree.3, daemon.3, dbopen.3, err.3, exec.3, fclose.3, ferror.3, fflush.3, fopen.3, fread.3, fseek.3, fts.3, hash.3, mpool.3, popen.3, queue.3, rcmd.3, recno.3, rexec.3, scanf.3, setbuf.3, stdarg.3, stdio.3, strtod.3, hostname.7, mdoc.7, mdoc.samples.7: srcfix: LICENSE: s/BSD_4_CLAUSE_FULL/BSD_4_CLAUSE_UCB/
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-10 16:41:19 +00:00
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.\" %%%LICENSE_START(BSD_4_CLAUSE_UCB)
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2004-11-03 13:51:07 +00:00
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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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accept.2, bind.2, connect.2, getpeername.2, getpriority.2, getsockname.2, getsockopt.2, ioctl.2, killpg.2, listen.2, lseek.2, readlink.2, recv.2, send.2, setpgid.2, setreuid.2, shutdown.2, socket.2, socketpair.2, syscall.2, truncate.2, alloca.3, btree.3, daemon.3, dbopen.3, err.3, exec.3, fclose.3, ferror.3, fflush.3, fopen.3, fread.3, fseek.3, fts.3, getloadavg.3, hash.3, mpool.3, openpty.3, popen.3, queue.3, rcmd.3, recno.3, rexec.3, scanf.3, setbuf.3, stdarg.3, stdio.3, strtod.3, hostname.7, mdoc.7, mdoc.samples.7, operator.7, symlink.7: Add LICENSE_START(BSD_[34]_CLAUSE_FULL)
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-10 09:28:48 +00:00
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.\" %%%LICENSE_END
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2004-11-03 13:51:07 +00:00
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.\"
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.\" $Id: recv.2,v 1.3 1999/05/13 11:33:38 freitag Exp $
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.\"
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.\" Modified Sat Jul 24 00:22:20 1993 by Rik Faith <faith@cs.unc.edu>
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.\" Modified Tue Oct 22 17:45:19 1996 by Eric S. Raymond <esr@thyrsus.com>
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.\" Modified 1998,1999 by Andi Kleen
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.\" 2001-06-19 corrected SO_EE_OFFENDER, bug report by James Hawtin
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.\"
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bind.2, connect.2, create_module.2, delete_module.2, execve.2, get_robust_list.2, getpriority.2, getrusage.2, init_module.2, link.2, listen.2, mbind.2, open.2, poll.2, query_module.2, readlink.2, recv.2, remap_file_pages.2, sched_setaffinity.2, semop.2, send.2, stat.2, stime.2, syscall.2, pthread_attr_setstackaddr.3, pthread_attr_setstacksize.3, remquo.3, rtime.3, sched_getcpu.3, stpcpy.3, stpncpy.3, strcasecmp.3, system.3, fd.4, proc.5, ip.7: tstamp
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2014-05-08 09:31:12 +00:00
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.TH RECV 2 2014-05-10 "Linux" "Linux Programmer's Manual"
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2004-11-03 13:51:07 +00:00
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.SH NAME
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recv, recvfrom, recvmsg \- receive a message from a socket
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.SH SYNOPSIS
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.\" .B #include <sys/uio.h>
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.\" .br
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2006-03-31 22:12:10 +00:00
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.nf
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2004-11-03 13:51:07 +00:00
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.B #include <sys/types.h>
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.br
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.B #include <sys/socket.h>
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.sp
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2008-12-03 18:56:22 +00:00
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.BI "ssize_t recv(int " sockfd ", void *" buf ", size_t " len ", int " flags );
|
2004-11-03 13:51:07 +00:00
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.sp
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2008-12-03 18:56:22 +00:00
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.BI "ssize_t recvfrom(int " sockfd ", void *" buf ", size_t " len ", int " flags ,
|
2008-12-03 20:42:47 +00:00
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.BI " struct sockaddr *" src_addr ", socklen_t *" addrlen );
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2004-11-03 13:51:07 +00:00
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.sp
|
2008-12-03 18:56:22 +00:00
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.BI "ssize_t recvmsg(int " sockfd ", struct msghdr *" msg ", int " flags );
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2006-03-31 22:12:10 +00:00
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.fi
|
2004-11-03 13:51:07 +00:00
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.SH DESCRIPTION
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The
|
2014-02-11 09:19:43 +00:00
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.BR recv (),
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.BR recvfrom (),
|
2004-11-03 13:51:07 +00:00
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and
|
2005-10-19 06:54:38 +00:00
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.BR recvmsg ()
|
2014-02-11 09:59:41 +00:00
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|
calls are used to receive messages from a socket.
|
2014-02-11 09:19:43 +00:00
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They may be used
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|
to receive data on both connectionless and connection-oriented sockets.
|
2014-02-11 09:29:58 +00:00
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|
This page first describes common features of all three system calls,
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|
and then describes the differences between the calls.
|
2004-11-03 13:51:07 +00:00
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|
.PP
|
2014-02-11 09:59:41 +00:00
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All three calls return the length of the message on successful
|
2007-04-12 22:42:49 +00:00
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completion.
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If a message is too long to fit in the supplied buffer, excess
|
2004-11-03 13:51:07 +00:00
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|
bytes may be discarded depending on the type of socket the message is
|
2006-03-31 22:58:00 +00:00
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|
received from.
|
2004-11-03 13:51:07 +00:00
|
|
|
.PP
|
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|
|
If no messages are available at the socket, the receive calls wait for a
|
accept.2, connect.2, eventfd.2, flock.2, open.2, posix_fadvise.2, read.2, recv.2, sched_setscheduler.2, select_tut.2, send.2, signalfd.2, splice.2, timerfd_create.2, write.2, flockfile.3, mkfifo.3, mq_notify.3, mq_open.3, pthread_tryjoin_np.3, scanf.3, random.4, ddp.7, epoll.7, fifo.7, ip.7, pipe.7, socket.7, spufs.7: Global fix: s/non-blocking/nonblocking/
The tendency in English, as prescribed in style guides like
Chicago MoS, is towards removing hyphens after prefixes
like "non-" etc.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2010-01-16 16:43:10 +00:00
|
|
|
message to arrive, unless the socket is nonblocking (see
|
2006-01-13 07:56:23 +00:00
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|
|
.BR fcntl (2)),
|
2004-11-03 13:51:07 +00:00
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|
in which case the value \-1 is returned and the external variable
|
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|
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.I errno
|
2009-02-23 04:57:43 +00:00
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|
is set to
|
2009-09-27 07:26:30 +00:00
|
|
|
.BR EAGAIN " or " EWOULDBLOCK .
|
2004-11-03 13:51:07 +00:00
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|
The receive calls normally return any data available, up to the requested
|
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|
amount, rather than waiting for receipt of the full amount requested.
|
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.PP
|
2014-05-03 08:28:28 +00:00
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An application can use
|
2014-02-11 09:22:25 +00:00
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.BR select (2),
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.BR poll (2),
|
2004-11-03 13:51:07 +00:00
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or
|
2014-02-11 09:22:25 +00:00
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.BR epoll (7)
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to determine when more data arrives on a socket.
|
2014-02-11 09:29:58 +00:00
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.SS The flags argument
|
2004-11-03 13:51:07 +00:00
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The
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.I flags
|
2014-02-11 09:20:16 +00:00
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argument is formed by ORing one or more of the following values:
|
2004-11-03 13:51:07 +00:00
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|
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.TP
|
2007-09-10 04:35:02 +00:00
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|
|
.BR MSG_CMSG_CLOEXEC " (" recvmsg "() only; since Linux 2.6.23)"
|
|
|
|
Set the close-on-exec flag for the file descriptor received
|
intro.1, time.1, accept.2, bind.2, connect.2, execve.2, flock.2, getdents.2, getpriority.2, getuid.2, intro.2, ioctl.2, mincore.2, mknod.2, personality.2, ptrace.2, read.2, recv.2, select_tut.2, send.2, sendfile.2, shmctl.2, sigaction.2, signal.2, stat.2, times.2, truncate.2, umask.2, wait.2, MB_CUR_MAX.3, MB_LEN_MAX.3, argz_add.3, btowc.3, clearenv.3, clock.3, cmsg.3, end.3, endian.3, errno.3, exit.3, fgetwc.3, fgetws.3, fopen.3, fputwc.3, fputws.3, fseek.3, fwide.3, getfsent.3, getgrnam.3, gethostid.3, getipnodebyname.3, getmntent.3, getpwnam.3, getwchar.3, grantpt.3, iconv.3, iconv_close.3, iconv_open.3, insque.3, intro.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, malloc.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, mkstemp.3, mktemp.3, nl_langinfo.3, openpty.3, posix_openpt.3, printf.3, ptsname.3, putwchar.3, qecvt.3, rcmd.3, readdir.3, rexec.3, rpc.3, setnetgrent.3, shm_open.3, sigpause.3, stdin.3, stpcpy.3, strftime.3, strptime.3, syslog.3, towctrans.3, towlower.3, towupper.3, ttyslot.3, ungetwc.3, unlocked_stdio.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wprintf.3, console_ioctl.4, pts.4, elf.5, filesystems.5, hosts.5, proc.5, ttytype.5, boot.7, capabilities.7, credentials.7, epoll.7, glob.7, koi8-r.7, path_resolution.7, pty.7, signal.7, suffixes.7, time.7, unicode.7, unix.7, uri.7, utf-8.7: global fix: s/Unix/UNIX/
The man pages were rather inconsistent in the use of "Unix"
versus "UNIX". Let's go with the trademark usage.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2010-10-12 04:45:38 +00:00
|
|
|
via a UNIX domain file descriptor using the
|
2007-09-20 16:26:31 +00:00
|
|
|
.B SCM_RIGHTS
|
2007-09-10 04:35:02 +00:00
|
|
|
operation (described in
|
|
|
|
.BR unix (7)).
|
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|
|
This flag is useful for the same reasons as the
|
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|
|
.B O_CLOEXEC
|
|
|
|
flag of
|
|
|
|
.BR open (2).
|
|
|
|
.TP
|
2008-07-14 05:26:06 +00:00
|
|
|
.BR MSG_DONTWAIT " (since Linux 2.2)"
|
accept.2, connect.2, eventfd.2, flock.2, open.2, posix_fadvise.2, read.2, recv.2, sched_setscheduler.2, select_tut.2, send.2, signalfd.2, splice.2, timerfd_create.2, write.2, flockfile.3, mkfifo.3, mq_notify.3, mq_open.3, pthread_tryjoin_np.3, scanf.3, random.4, ddp.7, epoll.7, fifo.7, ip.7, pipe.7, socket.7, spufs.7: Global fix: s/non-blocking/nonblocking/
The tendency in English, as prescribed in style guides like
Chicago MoS, is towards removing hyphens after prefixes
like "non-" etc.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2010-01-16 16:43:10 +00:00
|
|
|
Enables nonblocking operation; if the operation would block,
|
2008-04-18 16:17:12 +00:00
|
|
|
the call fails with the error
|
2009-02-23 04:57:43 +00:00
|
|
|
.BR EAGAIN " or " EWOULDBLOCK
|
2008-04-18 16:17:12 +00:00
|
|
|
(this can also be enabled using the
|
2006-01-13 07:56:23 +00:00
|
|
|
.B O_NONBLOCK
|
2009-02-23 04:57:43 +00:00
|
|
|
flag with the
|
2006-01-13 07:56:23 +00:00
|
|
|
.B F_SETFL
|
|
|
|
.BR fcntl (2)).
|
|
|
|
.TP
|
2008-09-29 09:46:01 +00:00
|
|
|
.BR MSG_ERRQUEUE " (since Linux 2.2)"
|
2004-11-03 13:51:07 +00:00
|
|
|
This flag
|
|
|
|
specifies that queued errors should be received from the socket error queue.
|
|
|
|
The error is passed in
|
|
|
|
an ancillary message with a type dependent on the protocol (for IPv4
|
|
|
|
.BR IP_RECVERR ).
|
2007-04-12 22:42:49 +00:00
|
|
|
The user should supply a buffer of sufficient size.
|
|
|
|
See
|
2004-11-03 13:51:07 +00:00
|
|
|
.BR cmsg (3)
|
|
|
|
and
|
|
|
|
.BR ip (7)
|
|
|
|
for more information.
|
|
|
|
The payload of the original packet that caused the error
|
|
|
|
is passed as normal data via
|
2006-03-12 19:09:15 +00:00
|
|
|
.IR msg_iovec .
|
2004-11-03 13:51:07 +00:00
|
|
|
The original destination address of the datagram that caused the error
|
|
|
|
is supplied via
|
2006-03-12 19:09:15 +00:00
|
|
|
.IR msg_name .
|
2004-11-03 13:51:07 +00:00
|
|
|
.IP
|
|
|
|
For local errors, no address is passed (this can be checked with the
|
|
|
|
.I cmsg_len
|
|
|
|
member of the
|
2006-03-12 19:09:15 +00:00
|
|
|
.IR cmsghdr ).
|
2004-11-03 13:51:07 +00:00
|
|
|
For error receives, the
|
|
|
|
.B MSG_ERRQUEUE
|
|
|
|
is set in the
|
2006-03-12 19:09:15 +00:00
|
|
|
.IR msghdr .
|
2004-11-03 13:51:07 +00:00
|
|
|
After an error has been passed, the pending socket error
|
|
|
|
is regenerated based on the next queued error and will be passed
|
|
|
|
on the next socket operation.
|
|
|
|
|
2007-04-12 22:42:49 +00:00
|
|
|
The error is supplied in a
|
2006-03-12 19:09:15 +00:00
|
|
|
.I sock_extended_err
|
2004-11-03 13:51:07 +00:00
|
|
|
structure:
|
2007-12-19 05:53:30 +00:00
|
|
|
.in +4n
|
2004-11-03 13:51:07 +00:00
|
|
|
.nf
|
2006-03-12 19:09:15 +00:00
|
|
|
|
|
|
|
#define SO_EE_ORIGIN_NONE 0
|
|
|
|
#define SO_EE_ORIGIN_LOCAL 1
|
|
|
|
#define SO_EE_ORIGIN_ICMP 2
|
|
|
|
#define SO_EE_ORIGIN_ICMP6 3
|
2004-11-03 13:51:07 +00:00
|
|
|
|
|
|
|
struct sock_extended_err
|
|
|
|
{
|
2007-12-23 17:26:26 +00:00
|
|
|
uint32_t ee_errno; /* error number */
|
|
|
|
uint8_t ee_origin; /* where the error originated */
|
|
|
|
uint8_t ee_type; /* type */
|
|
|
|
uint8_t ee_code; /* code */
|
2008-06-18 12:57:21 +00:00
|
|
|
uint8_t ee_pad; /* padding */
|
2007-12-23 17:26:26 +00:00
|
|
|
uint32_t ee_info; /* additional information */
|
|
|
|
uint32_t ee_data; /* other data */
|
2007-04-12 22:42:49 +00:00
|
|
|
/* More data may follow */
|
2004-11-03 13:51:07 +00:00
|
|
|
};
|
|
|
|
|
|
|
|
struct sockaddr *SO_EE_OFFENDER(struct sock_extended_err *);
|
|
|
|
.fi
|
2007-12-19 05:53:30 +00:00
|
|
|
.in
|
2004-11-03 13:51:07 +00:00
|
|
|
.IP
|
2007-06-23 07:19:07 +00:00
|
|
|
.I ee_errno
|
2007-06-22 06:05:43 +00:00
|
|
|
contains the
|
|
|
|
.I errno
|
|
|
|
number of the queued error.
|
2007-06-23 07:19:07 +00:00
|
|
|
.I ee_origin
|
2007-04-12 22:42:49 +00:00
|
|
|
is the origin code of where the error originated.
|
2007-12-25 21:30:22 +00:00
|
|
|
The other fields are protocol-specific.
|
2007-04-12 22:42:49 +00:00
|
|
|
The macro
|
|
|
|
.B SOCK_EE_OFFENDER
|
2004-11-03 13:51:07 +00:00
|
|
|
returns a pointer to the address of the network object
|
|
|
|
where the error originated from given a pointer to the ancillary message.
|
|
|
|
If this address is not known, the
|
2007-04-12 22:42:49 +00:00
|
|
|
.I sa_family
|
|
|
|
member of the
|
2007-06-23 07:19:07 +00:00
|
|
|
.I sockaddr
|
2007-04-12 22:42:49 +00:00
|
|
|
contains
|
2004-11-03 13:51:07 +00:00
|
|
|
.B AF_UNSPEC
|
2007-04-12 22:42:49 +00:00
|
|
|
and the other fields of the
|
2007-06-23 07:19:07 +00:00
|
|
|
.I sockaddr
|
2007-04-12 22:42:49 +00:00
|
|
|
are undefined.
|
|
|
|
The payload of the packet that caused the error is passed as normal data.
|
2004-11-03 13:51:07 +00:00
|
|
|
.IP
|
|
|
|
For local errors, no address is passed (this
|
2007-04-12 22:42:49 +00:00
|
|
|
can be checked with the
|
|
|
|
.I cmsg_len
|
|
|
|
member of the
|
|
|
|
.IR cmsghdr ).
|
2004-11-03 13:51:07 +00:00
|
|
|
For error receives,
|
2007-04-12 22:42:49 +00:00
|
|
|
the
|
2008-09-29 09:46:01 +00:00
|
|
|
.B MSG_ERRQUEUE
|
2007-04-12 22:42:49 +00:00
|
|
|
is set in the
|
|
|
|
.IR msghdr .
|
2004-11-03 13:51:07 +00:00
|
|
|
After an error has been passed, the pending socket error
|
|
|
|
is regenerated based on the next queued error and will be passed
|
|
|
|
on the next socket operation.
|
2005-12-14 16:44:39 +00:00
|
|
|
.TP
|
|
|
|
.B MSG_OOB
|
|
|
|
This flag requests receipt of out-of-band data that would not be received
|
2007-04-12 22:42:49 +00:00
|
|
|
in the normal data stream.
|
|
|
|
Some protocols place expedited data
|
2005-12-14 16:44:39 +00:00
|
|
|
at the head of the normal data queue, and thus this flag cannot
|
|
|
|
be used with such protocols.
|
|
|
|
.TP
|
|
|
|
.B MSG_PEEK
|
2007-04-12 22:42:49 +00:00
|
|
|
This flag causes the receive operation to
|
|
|
|
return data from the beginning of the
|
|
|
|
receive queue without removing that data from the queue.
|
|
|
|
Thus, a
|
2005-12-14 16:44:39 +00:00
|
|
|
subsequent receive call will return the same data.
|
|
|
|
.TP
|
2008-07-14 05:26:06 +00:00
|
|
|
.BR MSG_TRUNC " (since Linux 2.2)"
|
2008-12-01 16:26:48 +00:00
|
|
|
For raw
|
|
|
|
.RB ( AF_PACKET ),
|
|
|
|
Internet datagram (since Linux 2.4.27/2.6.8),
|
2014-02-27 21:37:27 +00:00
|
|
|
netlink (since Linux 2.6.22), and UNIX datagram (since Linux 3.4) sockets:
|
2008-12-01 16:26:48 +00:00
|
|
|
return the real length of the packet or datagram,
|
|
|
|
even when it was longer than the passed buffer.
|
|
|
|
|
|
|
|
For use with Internet stream sockets, see
|
|
|
|
.BR tcp (7).
|
2005-12-14 16:44:39 +00:00
|
|
|
.TP
|
2008-07-14 05:26:06 +00:00
|
|
|
.BR MSG_WAITALL " (since Linux 2.2)"
|
2005-12-14 16:44:39 +00:00
|
|
|
This flag requests that the operation block until the full request is
|
2007-04-12 22:42:49 +00:00
|
|
|
satisfied.
|
|
|
|
However, the call may still return less data than requested if
|
2005-12-14 16:44:39 +00:00
|
|
|
a signal is caught, an error or disconnect occurs, or the next data to be
|
|
|
|
received is of a different type than that returned.
|
2014-02-11 09:55:32 +00:00
|
|
|
.\"
|
2014-02-11 09:27:19 +00:00
|
|
|
.SS recvfrom()
|
2014-02-11 09:50:22 +00:00
|
|
|
.BR recvfrom ()
|
|
|
|
places the received message into the buffer
|
|
|
|
.IR buf .
|
|
|
|
The caller must specify the size of the buffer in
|
|
|
|
.IR len .
|
|
|
|
|
2014-02-11 09:27:19 +00:00
|
|
|
If
|
|
|
|
.I src_addr
|
2014-02-11 09:44:38 +00:00
|
|
|
is not NULL,
|
|
|
|
and the underlying protocol provides the source address of the message,
|
|
|
|
that source address is placed in the buffer pointed to by
|
|
|
|
.IR src_addr .
|
2014-02-11 09:27:19 +00:00
|
|
|
.\" (Note: for datagram sockets in both the UNIX and Internet domains,
|
|
|
|
.\" .I src_addr
|
|
|
|
.\" is filled in.
|
|
|
|
.\" .I src_addr
|
|
|
|
.\" is also filled in for stream sockets in the UNIX domain, but is not
|
|
|
|
.\" filled in for stream sockets in the Internet domain.)
|
|
|
|
.\" [The above notes on AF_UNIX and AF_INET sockets apply as at
|
|
|
|
.\" Kernel 2.4.18. (MTK, 22 Jul 02)]
|
2014-02-11 09:44:38 +00:00
|
|
|
In this case,
|
|
|
|
.I addrlen
|
|
|
|
is a value-result argument.
|
|
|
|
Before the call,
|
|
|
|
it should be initialized to the size of the buffer associated with
|
|
|
|
.IR src_addr .
|
|
|
|
Upon return,
|
2014-02-11 09:27:19 +00:00
|
|
|
.I addrlen
|
2014-02-11 09:44:38 +00:00
|
|
|
is updated to contain the actual size of the source address.
|
2014-02-11 09:27:19 +00:00
|
|
|
The returned address is truncated if the buffer provided is too small;
|
|
|
|
in this case,
|
|
|
|
.I addrlen
|
|
|
|
will return a value greater than was supplied to the call.
|
2014-02-11 09:44:38 +00:00
|
|
|
|
|
|
|
If the caller is not interested in the source address,
|
|
|
|
.I src_addr
|
2014-07-24 15:39:40 +00:00
|
|
|
and
|
2014-02-11 09:44:38 +00:00
|
|
|
.I addrlen
|
2014-07-24 15:39:40 +00:00
|
|
|
should be specified as NULL.
|
2014-02-11 09:55:32 +00:00
|
|
|
.\"
|
2014-02-11 09:27:19 +00:00
|
|
|
.SS recv()
|
|
|
|
The
|
|
|
|
.BR recv ()
|
|
|
|
call is normally used only on a
|
|
|
|
.I connected
|
|
|
|
socket (see
|
2014-02-11 09:57:41 +00:00
|
|
|
.BR connect (2)).
|
|
|
|
It is equivalent to the call:
|
|
|
|
|
|
|
|
recvfrom(fd, buf, len, flags, NULL, 0));
|
2014-02-11 09:55:32 +00:00
|
|
|
.\"
|
2014-02-11 09:27:19 +00:00
|
|
|
.SS recvmsg()
|
2004-11-03 13:51:07 +00:00
|
|
|
The
|
2005-10-19 06:54:38 +00:00
|
|
|
.BR recvmsg ()
|
2007-04-12 22:42:49 +00:00
|
|
|
call uses a
|
2004-11-03 13:51:07 +00:00
|
|
|
.I msghdr
|
2008-07-10 20:53:08 +00:00
|
|
|
structure to minimize the number of directly supplied arguments.
|
2009-03-09 22:02:58 +00:00
|
|
|
This structure is defined as follows in
|
2004-11-03 13:51:07 +00:00
|
|
|
.IR <sys/socket.h> :
|
2007-12-19 05:53:30 +00:00
|
|
|
.in +4n
|
2004-11-03 13:51:07 +00:00
|
|
|
.nf
|
2006-03-12 19:09:15 +00:00
|
|
|
|
2009-03-09 22:02:58 +00:00
|
|
|
struct iovec { /* Scatter/gather array items */
|
|
|
|
void *iov_base; /* Starting address */
|
|
|
|
size_t iov_len; /* Number of bytes to transfer */
|
|
|
|
};
|
|
|
|
|
2004-11-03 13:51:07 +00:00
|
|
|
struct msghdr {
|
2006-03-12 19:09:15 +00:00
|
|
|
void *msg_name; /* optional address */
|
|
|
|
socklen_t msg_namelen; /* size of address */
|
|
|
|
struct iovec *msg_iov; /* scatter/gather array */
|
|
|
|
size_t msg_iovlen; /* # elements in msg_iov */
|
|
|
|
void *msg_control; /* ancillary data, see below */
|
2010-08-29 06:29:04 +00:00
|
|
|
size_t msg_controllen; /* ancillary data buffer len */
|
2006-03-12 19:09:15 +00:00
|
|
|
int msg_flags; /* flags on received message */
|
2004-11-03 13:51:07 +00:00
|
|
|
};
|
|
|
|
.fi
|
2007-12-19 05:53:30 +00:00
|
|
|
.in
|
2004-11-03 13:51:07 +00:00
|
|
|
.PP
|
2014-05-03 08:18:31 +00:00
|
|
|
The
|
2004-11-03 13:51:07 +00:00
|
|
|
.I msg_name
|
2014-05-03 08:18:31 +00:00
|
|
|
field points to a caller-allocated buffer that is used to
|
|
|
|
return the source address if the socket is unconnected.
|
|
|
|
The caller should set
|
2004-11-03 13:51:07 +00:00
|
|
|
.I msg_namelen
|
2014-05-03 08:18:31 +00:00
|
|
|
to the size of this buffer before this call;
|
|
|
|
upon return from a successful call,
|
2004-11-03 13:51:07 +00:00
|
|
|
.I msg_name
|
2014-05-03 08:18:31 +00:00
|
|
|
will contain the length of the returned address.
|
|
|
|
If the application does not need to know the source address,
|
|
|
|
.I msg_name
|
|
|
|
can be specified as NULL.
|
|
|
|
|
2004-11-03 13:51:07 +00:00
|
|
|
The fields
|
|
|
|
.I msg_iov
|
|
|
|
and
|
|
|
|
.I msg_iovlen
|
|
|
|
describe scatter-gather locations, as discussed in
|
|
|
|
.BR readv (2).
|
2014-05-03 07:30:14 +00:00
|
|
|
|
2004-11-03 13:51:07 +00:00
|
|
|
The field
|
|
|
|
.IR msg_control ,
|
|
|
|
which has length
|
|
|
|
.IR msg_controllen ,
|
2007-06-02 05:49:27 +00:00
|
|
|
points to a buffer for other protocol control-related messages or
|
2007-04-12 22:42:49 +00:00
|
|
|
miscellaneous ancillary data.
|
|
|
|
When
|
2005-10-19 06:54:38 +00:00
|
|
|
.BR recvmsg ()
|
2007-04-12 22:42:49 +00:00
|
|
|
is called,
|
2004-11-03 13:51:07 +00:00
|
|
|
.I msg_controllen
|
2007-04-12 22:42:49 +00:00
|
|
|
should contain the length of the available buffer in
|
|
|
|
.IR msg_control ;
|
2004-11-03 13:51:07 +00:00
|
|
|
upon return from a successful call it will contain the length
|
|
|
|
of the control message sequence.
|
|
|
|
.PP
|
|
|
|
The messages are of the form:
|
2007-12-19 05:53:30 +00:00
|
|
|
.in +4n
|
2004-11-03 13:51:07 +00:00
|
|
|
.nf
|
2006-03-12 19:09:15 +00:00
|
|
|
|
2004-11-03 13:51:07 +00:00
|
|
|
struct cmsghdr {
|
2007-12-23 17:26:26 +00:00
|
|
|
socklen_t cmsg_len; /* data byte count, including hdr */
|
|
|
|
int cmsg_level; /* originating protocol */
|
|
|
|
int cmsg_type; /* protocol-specific type */
|
2004-11-03 13:51:07 +00:00
|
|
|
/* followed by
|
2007-12-23 17:26:26 +00:00
|
|
|
unsigned char cmsg_data[]; */
|
2004-11-03 13:51:07 +00:00
|
|
|
};
|
|
|
|
.fi
|
2007-12-19 05:53:30 +00:00
|
|
|
.in
|
2004-11-03 13:51:07 +00:00
|
|
|
.PP
|
intro.1, _syscall.2, access.2, arch_prctl.2, cacheflush.2, chown.2, clock_getres.2, clone.2, create_module.2, fcntl.2, flock.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getpriority.2, getrlimit.2, getrusage.2, ioprio_set.2, kexec_load.2, madvise.2, mbind.2, migrate_pages.2, mknod.2, mmap.2, mount.2, move_pages.2, mprotect.2, open.2, pause.2, pciconfig_read.2, perf_event_open.2, prctl.2, ptrace.2, query_module.2, read.2, reboot.2, recv.2, s390_runtime_instr.2, sched_setscheduler.2, select_tut.2, send.2, set_mempolicy.2, setfsgid.2, setfsuid.2, sigaction.2, spu_create.2, spu_run.2, stime.2, swapon.2, syslog.2, timer_create.2, timer_getoverrun.2, times.2, tkill.2, umount.2, unimplemented.2, ustat.2, vm86.2, wait.2, abs.3, aio_read.3, aio_write.3, bsd_signal.3, catgets.3, clearenv.3, cmsg.3, dbopen.3, dirfd.3, dlopen.3, exec.3, fenv.3, ferror.3, fmemopen.3, fnmatch.3, fopen.3, futimes.3, getaddrinfo.3, getifaddrs.3, getipnodebyname.3, hsearch.3, if_nameindex.3, inet_pton.3, mblen.3, mbrlen.3, mbsrtowcs.3, mbtowc.3, mcheck.3, memfrob.3, mq_notify.3, netlink.3, posix_memalign.3, printf.3, pthread_attr_setscope.3, pthread_cleanup_push.3, pthread_kill_other_threads_np.3, pthread_self.3, pthread_setcancelstate.3, pthread_setconcurrency.3, raise.3, resolver.3, rpc.3, rtime.3, rtnetlink.3, scanf.3, setbuf.3, setnetgrent.3, shm_open.3, sigpause.3, sigset.3, sigwait.3, sockatmark.3, strcasecmp.3, strcmp.3, strdup.3, strftime.3, strptime.3, strsignal.3, strverscmp.3, sysv_signal.3, termios.3, wcrtomb.3, wcsnlen.3, wcsnrtombs.3, wcsrtombs.3, wctomb.3, wprintf.3, console_codes.4, cpuid.4, msr.4, rtc.4, sk98lin.4, st.4, tty.4, charmap.5, core.5, elf.5, hosts.equiv.5, proc.5, resolv.conf.5, services.5, slabinfo.5, arp.7, bootparam.7, capabilities.7, charsets.7, cpuset.7, ddp.7, epoll.7, feature_test_macros.7, futex.7, hier.7, icmp.7, inotify.7, ip.7, ipv6.7, man-pages.7, mdoc.7, mdoc.samples.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, posixoptions.7, pthreads.7, raw.7, rtld-audit.7, rtnetlink.7, sem_overview.7, sigevent.7, socket.7, spufs.7, tcp.7, udp.7, unicode.7, uri.7, utf-8.7, intro.8, ldconfig.8, sync.8: Global fix: fix placement of word "only"
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-31 08:53:00 +00:00
|
|
|
Ancillary data should be accessed only by the macros defined in
|
2004-11-03 13:51:07 +00:00
|
|
|
.BR cmsg (3).
|
|
|
|
.PP
|
2010-06-12 12:42:50 +00:00
|
|
|
As an example, Linux uses this ancillary data mechanism to pass extended
|
2010-10-12 04:48:33 +00:00
|
|
|
errors, IP options, or file descriptors over UNIX domain sockets.
|
2004-11-03 13:51:07 +00:00
|
|
|
.PP
|
|
|
|
The
|
|
|
|
.I msg_flags
|
2011-09-08 14:04:04 +00:00
|
|
|
field in the
|
|
|
|
.I msghdr
|
|
|
|
is set on return of
|
2004-11-03 13:51:07 +00:00
|
|
|
.BR recvmsg ().
|
|
|
|
It can contain several flags:
|
|
|
|
.TP
|
|
|
|
.B MSG_EOR
|
|
|
|
indicates end-of-record; the data returned completed a record (generally
|
|
|
|
used with sockets of type
|
|
|
|
.BR SOCK_SEQPACKET ).
|
|
|
|
.TP
|
|
|
|
.B MSG_TRUNC
|
|
|
|
indicates that the trailing portion of a datagram was discarded because the
|
|
|
|
datagram was larger than the buffer supplied.
|
|
|
|
.TP
|
|
|
|
.B MSG_CTRUNC
|
|
|
|
indicates that some control data were discarded due to lack of space in the
|
|
|
|
buffer for ancillary data.
|
|
|
|
.TP
|
|
|
|
.B MSG_OOB
|
|
|
|
is returned to indicate that expedited or out-of-band data were received.
|
|
|
|
.TP
|
|
|
|
.B MSG_ERRQUEUE
|
|
|
|
indicates that no data was received but an extended error from the socket
|
|
|
|
error queue.
|
getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
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.SH RETURN VALUE
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2004-11-03 13:51:07 +00:00
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These calls return the number of bytes received, or \-1
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2007-04-12 22:42:49 +00:00
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if an error occurred.
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2013-04-19 06:32:47 +00:00
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In the event of an error,
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.I errno
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is set to indicate the error.
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2014-02-11 10:13:36 +00:00
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When a stream socket peer has performed an orderly shutdown,
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the return value will be 0 (the traditional "end-of-file" return).
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Datagram sockets in various domains (e.g., the UNIX and Internet domains)
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permit zero-length datagrams.
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When such a datagram is received, the return value is 0.
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The value 0 may also be returned if the requested number of bytes
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to receive from a stream socket was 0.
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2004-11-03 13:51:07 +00:00
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.SH ERRORS
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2007-04-12 22:42:49 +00:00
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These are some standard errors generated by the socket layer.
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Additional errors
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may be generated and returned from the underlying protocol modules;
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see their manual pages.
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2004-11-03 13:51:07 +00:00
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.TP
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2009-02-23 04:57:43 +00:00
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.BR EAGAIN " or " EWOULDBLOCK
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.\" Actually EAGAIN on Linux
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accept.2, connect.2, eventfd.2, flock.2, open.2, posix_fadvise.2, read.2, recv.2, sched_setscheduler.2, select_tut.2, send.2, signalfd.2, splice.2, timerfd_create.2, write.2, flockfile.3, mkfifo.3, mq_notify.3, mq_open.3, pthread_tryjoin_np.3, scanf.3, random.4, ddp.7, epoll.7, fifo.7, ip.7, pipe.7, socket.7, spufs.7: Global fix: s/non-blocking/nonblocking/
The tendency in English, as prescribed in style guides like
Chicago MoS, is towards removing hyphens after prefixes
like "non-" etc.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2010-01-16 16:43:10 +00:00
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The socket is marked nonblocking and the receive operation
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2004-11-03 13:51:07 +00:00
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would block, or a receive timeout had been set and the timeout expired
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before data was received.
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2009-02-23 04:57:43 +00:00
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POSIX.1-2001 allows either error to be returned for this case,
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and does not require these constants to have the same value,
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so a portable application should check for both possibilities.
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2004-11-03 13:51:07 +00:00
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.TP
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.B EBADF
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The argument
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2008-12-03 21:01:54 +00:00
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.I sockfd
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2004-11-03 13:51:07 +00:00
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is an invalid descriptor.
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.TP
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.B ECONNREFUSED
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A remote host refused to allow the network connection (typically
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because it is not running the requested service).
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.TP
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.B EFAULT
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The receive buffer pointer(s) point outside the process's
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address space.
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.TP
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.B EINTR
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The receive was interrupted by delivery of a signal before
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2008-07-04 15:50:36 +00:00
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any data were available; see
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.BR signal (7).
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2004-11-03 13:51:07 +00:00
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.TP
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.B EINVAL
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2007-04-12 22:42:49 +00:00
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Invalid argument passed.
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2008-12-03 20:42:47 +00:00
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.\" e.g., msg_namelen < 0 for recvmsg() or addrlen < 0 for recvfrom()
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2004-11-03 13:51:07 +00:00
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.TP
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.B ENOMEM
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2007-04-12 22:42:49 +00:00
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Could not allocate memory for
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.BR recvmsg ().
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2004-11-03 13:51:07 +00:00
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.TP
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.B ENOTCONN
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The socket is associated with a connection-oriented protocol
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and has not been connected (see
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.BR connect (2)
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and
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.BR accept (2)).
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.TP
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.B ENOTSOCK
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The argument
|
2008-12-03 21:01:54 +00:00
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.I sockfd
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2004-11-03 13:51:07 +00:00
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does not refer to a socket.
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getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
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.SH CONFORMING TO
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2004-11-03 13:51:07 +00:00
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4.4BSD (these function calls first appeared in 4.2BSD),
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2006-08-03 13:57:17 +00:00
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POSIX.1-2001.
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2004-11-03 13:51:07 +00:00
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.LP
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intro.1, _syscall.2, access.2, arch_prctl.2, cacheflush.2, chown.2, clock_getres.2, clone.2, create_module.2, fcntl.2, flock.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getpriority.2, getrlimit.2, getrusage.2, ioprio_set.2, kexec_load.2, madvise.2, mbind.2, migrate_pages.2, mknod.2, mmap.2, mount.2, move_pages.2, mprotect.2, open.2, pause.2, pciconfig_read.2, perf_event_open.2, prctl.2, ptrace.2, query_module.2, read.2, reboot.2, recv.2, s390_runtime_instr.2, sched_setscheduler.2, select_tut.2, send.2, set_mempolicy.2, setfsgid.2, setfsuid.2, sigaction.2, spu_create.2, spu_run.2, stime.2, swapon.2, syslog.2, timer_create.2, timer_getoverrun.2, times.2, tkill.2, umount.2, unimplemented.2, ustat.2, vm86.2, wait.2, abs.3, aio_read.3, aio_write.3, bsd_signal.3, catgets.3, clearenv.3, cmsg.3, dbopen.3, dirfd.3, dlopen.3, exec.3, fenv.3, ferror.3, fmemopen.3, fnmatch.3, fopen.3, futimes.3, getaddrinfo.3, getifaddrs.3, getipnodebyname.3, hsearch.3, if_nameindex.3, inet_pton.3, mblen.3, mbrlen.3, mbsrtowcs.3, mbtowc.3, mcheck.3, memfrob.3, mq_notify.3, netlink.3, posix_memalign.3, printf.3, pthread_attr_setscope.3, pthread_cleanup_push.3, pthread_kill_other_threads_np.3, pthread_self.3, pthread_setcancelstate.3, pthread_setconcurrency.3, raise.3, resolver.3, rpc.3, rtime.3, rtnetlink.3, scanf.3, setbuf.3, setnetgrent.3, shm_open.3, sigpause.3, sigset.3, sigwait.3, sockatmark.3, strcasecmp.3, strcmp.3, strdup.3, strftime.3, strptime.3, strsignal.3, strverscmp.3, sysv_signal.3, termios.3, wcrtomb.3, wcsnlen.3, wcsnrtombs.3, wcsrtombs.3, wctomb.3, wprintf.3, console_codes.4, cpuid.4, msr.4, rtc.4, sk98lin.4, st.4, tty.4, charmap.5, core.5, elf.5, hosts.equiv.5, proc.5, resolv.conf.5, services.5, slabinfo.5, arp.7, bootparam.7, capabilities.7, charsets.7, cpuset.7, ddp.7, epoll.7, feature_test_macros.7, futex.7, hier.7, icmp.7, inotify.7, ip.7, ipv6.7, man-pages.7, mdoc.7, mdoc.samples.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, posixoptions.7, pthreads.7, raw.7, rtld-audit.7, rtnetlink.7, sem_overview.7, sigevent.7, socket.7, spufs.7, tcp.7, udp.7, unicode.7, uri.7, utf-8.7, intro.8, ldconfig.8, sync.8: Global fix: fix placement of word "only"
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-03-31 08:53:00 +00:00
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POSIX.1-2001 describes only the
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2004-11-03 13:51:07 +00:00
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.BR MSG_OOB ,
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.BR MSG_PEEK ,
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and
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.B MSG_WAITALL
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flags.
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2006-03-12 19:09:15 +00:00
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.SH NOTES
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2014-06-29 08:09:47 +00:00
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The
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.I socklen_t
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type was invented by POSIX.
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2004-11-03 13:51:07 +00:00
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See also
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.BR accept (2).
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2006-03-12 19:09:15 +00:00
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According to POSIX.1-2001, the
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.I msg_controllen
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field of the
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.I msghdr
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structure should be typed as
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.IR socklen_t ,
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2010-08-29 06:32:22 +00:00
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but glibc currently types it as
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2006-03-12 19:09:15 +00:00
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.IR size_t .
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2006-04-03 01:35:31 +00:00
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.\" glibc bug raised 12 Mar 2006
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2006-03-12 19:09:15 +00:00
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.\" http://sourceware.org/bugzilla/show_bug.cgi?id=2448
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2006-04-03 01:35:31 +00:00
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.\" The problem is an underlying kernel issue: the size of the
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.\" __kernel_size_t type used to type this field varies
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.\" across architectures, but socklen_t is always 32 bits.
|
2011-09-10 15:48:49 +00:00
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See
|
2012-06-07 12:27:54 +00:00
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.BR recvmmsg (2)
|
2011-09-10 15:48:49 +00:00
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for information about a Linux-specific system call
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that can be used to receive multiple datagrams in a single call.
|
2007-05-28 10:53:03 +00:00
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.SH EXAMPLE
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An example of the use of
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.BR recvfrom ()
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is shown in
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.BR getaddrinfo (3).
|
getent.1, intro.1, time.1, _exit.2, _syscall.2, accept.2, access.2, acct.2, adjtimex.2, alarm.2, alloc_hugepages.2, arch_prctl.2, bdflush.2, bind.2, brk.2, cacheflush.2, capget.2, chdir.2, chmod.2, chown.2, chroot.2, clock_getres.2, clock_nanosleep.2, clone.2, close.2, connect.2, create_module.2, delete_module.2, dup.2, epoll_create.2, epoll_ctl.2, epoll_wait.2, eventfd.2, execve.2, exit_group.2, faccessat.2, fchmodat.2, fchownat.2, fcntl.2, flock.2, fork.2, fstatat.2, fsync.2, futex.2, futimesat.2, get_kernel_syms.2, get_robust_list.2, get_thread_area.2, getcpu.2, getdents.2, getdomainname.2, getgid.2, getgroups.2, gethostname.2, getitimer.2, getpagesize.2, getpeername.2, getpid.2, getpriority.2, getresuid.2, getrlimit.2, getrusage.2, getsid.2, getsockname.2, getsockopt.2, gettid.2, gettimeofday.2, getuid.2, getunwind.2, getxattr.2, idle.2, init_module.2, inotify_add_watch.2, inotify_init.2, inotify_rm_watch.2, intro.2, io_cancel.2, io_destroy.2, io_getevents.2, io_setup.2, io_submit.2, ioctl.2, ioctl_list.2, ioperm.2, iopl.2, ioprio_set.2, ipc.2, kcmp.2, kill.2, killpg.2, link.2, linkat.2, listen.2, listxattr.2, llseek.2, lookup_dcookie.2, lseek.2, madvise.2, migrate_pages.2, mincore.2, mkdir.2, mkdirat.2, mknod.2, mknodat.2, mlock.2, mmap.2, mmap2.2, modify_ldt.2, mount.2, move_pages.2, mprotect.2, mq_getsetattr.2, mremap.2, msgctl.2, msgget.2, msgop.2, msync.2, nanosleep.2, nfsservctl.2, nice.2, open.2, openat.2, outb.2, pause.2, pciconfig_read.2, perf_event_open.2, perfmonctl.2, personality.2, pipe.2, pivot_root.2, poll.2, posix_fadvise.2, prctl.2, pread.2, process_vm_readv.2, ptrace.2, query_module.2, quotactl.2, read.2, readahead.2, readdir.2, readlink.2, readlinkat.2, readv.2, reboot.2, recv.2, remap_file_pages.2, removexattr.2, rename.2, renameat.2, rmdir.2, rt_sigqueueinfo.2, sched_get_priority_max.2, sched_rr_get_interval.2, sched_setaffinity.2, sched_setparam.2, sched_setscheduler.2, sched_yield.2, select.2, semctl.2, semget.2, semop.2, send.2, sendfile.2, set_thread_area.2, set_tid_address.2, seteuid.2, setfsgid.2, setfsuid.2, setgid.2, setpgid.2, setresuid.2, setreuid.2, setsid.2, setuid.2, setup.2, setxattr.2, shmctl.2, shmget.2, shmop.2, shutdown.2, sigaction.2, sigaltstack.2, signal.2, signalfd.2, sigpending.2, sigprocmask.2, sigreturn.2, sigsuspend.2, sigwaitinfo.2, socket.2, socketcall.2, socketpair.2, splice.2, stat.2, statfs.2, stime.2, swapon.2, symlink.2, symlinkat.2, sync.2, sync_file_range.2, sysctl.2, sysfs.2, sysinfo.2, syslog.2, tee.2, time.2, timerfd_create.2, times.2, tkill.2, truncate.2, umask.2, umount.2, uname.2, unimplemented.2, unlink.2, unlinkat.2, uselib.2, ustat.2, utime.2, utimensat.2, vfork.2, vhangup.2, vm86.2, vmsplice.2, wait.2, wait4.2, write.2, CPU_SET.3, INFINITY.3, MB_CUR_MAX.3, MB_LEN_MAX.3, __setfpucw.3, a64l.3, abort.3, abs.3, acos.3, acosh.3, addseverity.3, adjtime.3, aio_cancel.3, aio_error.3, aio_fsync.3, aio_read.3, aio_return.3, aio_suspend.3, aio_write.3, alloca.3, argz_add.3, asin.3, asinh.3, asprintf.3, assert.3, assert_perror.3, atan.3, atan2.3, atanh.3, atexit.3, atof.3, atoi.3, backtrace.3, basename.3, bcmp.3, bcopy.3, bindresvport.3, bsd_signal.3, bsearch.3, bstring.3, btowc.3, btree.3, byteorder.3, bzero.3, cabs.3, cacos.3, cacosh.3, canonicalize_file_name.3, carg.3, casin.3, casinh.3, catan.3, catanh.3, catgets.3, catopen.3, cbrt.3, ccos.3, ccosh.3, ceil.3, cerf.3, cexp.3, cexp2.3, cfree.3, cimag.3, clearenv.3, clock.3, clock_getcpuclockid.3, clog.3, clog10.3, clog2.3, closedir.3, cmsg.3, confstr.3, conj.3, copysign.3, cos.3, cosh.3, cpow.3, cproj.3, creal.3, crypt.3, csin.3, csinh.3, csqrt.3, ctan.3, ctanh.3, ctermid.3, ctime.3, daemon.3, dbopen.3, des_crypt.3, difftime.3, dirfd.3, div.3, dl_iterate_phdr.3, dlopen.3, dprintf.3, drand48.3, drand48_r.3, dysize.3, ecvt.3, ecvt_r.3, encrypt.3, end.3, endian.3, envz_add.3, erf.3, erfc.3, err.3, errno.3, error.3, ether_aton.3, euidaccess.3, exec.3, exit.3, exp.3, exp10.3, exp2.3, expm1.3, fabs.3, fclose.3, fcloseall.3, fdim.3, fenv.3, ferror.3, fexecve.3, fflush.3, ffs.3, fgetgrent.3, fgetpwent.3, fgetwc.3, fgetws.3, finite.3, flockfile.3, floor.3, fma.3, fmax.3, fmemopen.3, fmin.3, fmod.3, fmtmsg.3, fnmatch.3, fopen.3, fpathconf.3, fpclassify.3, fpurge.3, fputwc.3, fputws.3, fread.3, frexp.3, fseek.3, fseeko.3, ftime.3, ftok.3, fts.3, ftw.3, futimes.3, fwide.3, gamma.3, gcvt.3, getaddrinfo.3, getaddrinfo_a.3, getauxval.3, getcontext.3, getcwd.3, getdate.3, getdirentries.3, getdtablesize.3, getenv.3, getfsent.3, getgrent.3, getgrent_r.3, getgrnam.3, getgrouplist.3, gethostbyname.3, gethostid.3, getipnodebyname.3, getline.3, getloadavg.3, getlogin.3, getmntent.3, getnameinfo.3, getnetent.3, getnetent_r.3, getopt.3, getpass.3, getprotoent.3, getprotoent_r.3, getpt.3, getpw.3, getpwent.3, getpwent_r.3, getpwnam.3, getrpcent.3, getrpcent_r.3, getrpcport.3, gets.3, getservent.3, getservent_r.3, getspnam.3, getttyent.3, getumask.3, getusershell.3, getutent.3, getw.3, getwchar.3, glob.3, grantpt.3, gsignal.3, hash.3, hsearch.3, hypot.3, iconv.3, iconv_close.3, iconv_open.3, ilogb.3, index.3, inet.3, inet_ntop.3, inet_pton.3, infnan.3, initgroups.3, insque.3, intro.3, isalpha.3, isatty.3, isgreater.3, iswalnum.3, iswalpha.3, iswblank.3, iswcntrl.3, iswctype.3, iswdigit.3, iswgraph.3, iswlower.3, iswprint.3, iswpunct.3, iswspace.3, iswupper.3, iswxdigit.3, j0.3, key_setsecret.3, ldexp.3, lgamma.3, lio_listio.3, localeconv.3, lockf.3, log.3, log10.3, log1p.3, log2.3, logb.3, login.3, longjmp.3, lrint.3, lround.3, lsearch.3, lseek64.3, makecontext.3, makedev.3, malloc.3, malloc_hook.3, mblen.3, mbrlen.3, mbrtowc.3, mbsinit.3, mbsnrtowcs.3, mbsrtowcs.3, mbstowcs.3, mbtowc.3, memccpy.3, memchr.3, memcmp.3, memcpy.3, memfrob.3, memmem.3, memmove.3, mempcpy.3, memset.3, mkdtemp.3, mkfifo.3, mkfifoat.3, mkstemp.3, mktemp.3, modf.3, mpool.3, mq_close.3, mq_getattr.3, mq_notify.3, mq_open.3, mq_receive.3, mq_send.3, mq_unlink.3, mtrace.3, nan.3, netlink.3, nextafter.3, nl_langinfo.3, offsetof.3, on_exit.3, opendir.3, openpty.3, perror.3, popen.3, posix_fallocate.3, posix_memalign.3, posix_openpt.3, pow.3, pow10.3, printf.3, profil.3, program_invocation_name.3, psignal.3, pthread_kill_other_threads_np.3, ptsname.3, putenv.3, putgrent.3, putpwent.3, puts.3, putwchar.3, qecvt.3, qsort.3, queue.3, raise.3, rand.3, random.3, random_r.3, rcmd.3, re_comp.3, readdir.3, realpath.3, recno.3, regex.3, remainder.3, remove.3, remquo.3, resolver.3, rewinddir.3, rexec.3, rint.3, round.3, rpc.3, rpmatch.3, rtime.3, rtnetlink.3, scalb.3, scalbln.3, scandir.3, scandirat.3, scanf.3, seekdir.3, sem_close.3, sem_destroy.3, sem_getvalue.3, sem_init.3, sem_open.3, sem_post.3, sem_unlink.3, sem_wait.3, setaliasent.3, setbuf.3, setenv.3, setjmp.3, setlocale.3, setlogmask.3, setnetgrent.3, shm_open.3, siginterrupt.3, signbit.3, significand.3, sigpause.3, sigqueue.3, sigset.3, sigsetops.3, sigvec.3, sin.3, sincos.3, sinh.3, sleep.3, sockatmark.3, sqrt.3, statvfs.3, stdarg.3, stdin.3, stdio.3, stdio_ext.3, stpcpy.3, stpncpy.3, strcasecmp.3, strcat.3, strchr.3, strcmp.3, strcoll.3, strcpy.3, strdup.3, strerror.3, strfmon.3, strfry.3, strftime.3, string.3, strlen.3, strnlen.3, strpbrk.3, strptime.3, strsep.3, strsignal.3, strspn.3, strstr.3, strtod.3, strtoimax.3, strtok.3, strtol.3, strtoul.3, strverscmp.3, strxfrm.3, swab.3, sysconf.3, syslog.3, system.3, sysv_signal.3, tan.3, tanh.3, tcgetpgrp.3, tcgetsid.3, telldir.3, tempnam.3, termios.3, tgamma.3, timegm.3, timeradd.3, tmpfile.3, tmpnam.3, toascii.3, toupper.3, towctrans.3, towlower.3, towupper.3, trunc.3, tsearch.3, ttyname.3, ttyslot.3, tzset.3, ualarm.3, ulimit.3, ungetwc.3, unlocked_stdio.3, unlockpt.3, updwtmp.3, usleep.3, wcpcpy.3, wcpncpy.3, wcrtomb.3, wcscasecmp.3, wcscat.3, wcschr.3, wcscmp.3, wcscpy.3, wcscspn.3, wcsdup.3, wcslen.3, wcsncasecmp.3, wcsncat.3, wcsncmp.3, wcsncpy.3, wcsnlen.3, wcsnrtombs.3, wcspbrk.3, wcsrchr.3, wcsrtombs.3, wcsspn.3, wcsstr.3, wcstoimax.3, wcstok.3, wcstombs.3, wcswidth.3, wctob.3, wctomb.3, wctrans.3, wctype.3, wcwidth.3, wmemchr.3, wmemcmp.3, wmemcpy.3, wmemmove.3, wmemset.3, wordexp.3, wprintf.3, xcrypt.3, xdr.3, y0.3, cciss.4, console.4, console_codes.4, console_ioctl.4, dsp56k.4, fd.4, full.4, hd.4, hpsa.4, initrd.4, intro.4, lp.4, mem.4, mouse.4, null.4, pts.4, ram.4, random.4, rtc.4, sk98lin.4, st.4, tty.4, ttyS.4, tty_ioctl.4, vcs.4, wavelan.4, acct.5, charmap.5, dir_colors.5, filesystems.5, ftpusers.5, group.5, host.conf.5, hosts.5, hosts.equiv.5, intro.5, issue.5, locale.5, motd.5, networks.5, nologin.5, nscd.conf.5, passwd.5, proc.5, protocols.5, resolv.conf.5, rpc.5, securetty.5, services.5, shells.5, termcap.5, ttytype.5, utmp.5, armscii-8.7, arp.7, ascii.7, bootparam.7, capabilities.7, charsets.7, complex.7, cp1251.7, credentials.7, ddp.7, environ.7, epoll.7, fifo.7, futex.7, glob.7, hier.7, icmp.7, inotify.7, intro.7, ip.7, ipv6.7, iso_8859-1.7, iso_8859-10.7, iso_8859-11.7, iso_8859-13.7, iso_8859-14.7, iso_8859-15.7, iso_8859-16.7, iso_8859-2.7, iso_8859-3.7, iso_8859-4.7, iso_8859-5.7, iso_8859-6.7, iso_8859-7.7, iso_8859-8.7, iso_8859-9.7, koi8-r.7, koi8-u.7, locale.7, mailaddr.7, man.7, mq_overview.7, netdevice.7, netlink.7, numa.7, packet.7, path_resolution.7, pipe.7, posixoptions.7, pthreads.7, pty.7, raw.7, regex.7, rtld-audit.7, rtnetlink.7, sem_overview.7, shm_overview.7, sigevent.7, signal.7, socket.7, standards.7, suffixes.7, svipc.7, tcp.7, termio.7, time.7, udp.7, udplite.7, unicode.7, unix.7, uri.7, utf-8.7, x25.7, nscd.8, sync.8, tzselect.8, zdump.8, zic.8: Global fix: remove unneeded double quotes in .SH headings
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
2013-02-24 18:01:36 +00:00
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.SH SEE ALSO
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2004-11-03 13:51:07 +00:00
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.BR fcntl (2),
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.BR getsockopt (2),
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.BR read (2),
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2011-09-10 15:48:49 +00:00
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.BR recvmmsg (2),
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2004-11-03 13:51:07 +00:00
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.BR select (2),
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2005-06-30 09:40:35 +00:00
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.BR shutdown (2),
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2004-11-03 13:51:07 +00:00
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.BR socket (2),
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2006-04-22 03:18:05 +00:00
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.BR cmsg (3),
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2008-12-01 15:26:37 +00:00
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.BR sockatmark (3),
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.BR socket (7)
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