fbbd9655e5
Renumber cluase 4 to 3, per what everybody else did when BSD granted them permission to remove clause 3. My insistance on keeping the same numbering for legal reasons is too pedantic, so give up on that point. Submitted by: Jan Schaumann <jschauma@stevens.edu> Pull Request: https://github.com/freebsd/freebsd/pull/96
186 lines
5.6 KiB
Groff
186 lines
5.6 KiB
Groff
.\" Copyright (c) 1983, 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. 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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.\" @(#)connect.2 8.1 (Berkeley) 6/4/93
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.\" $FreeBSD$
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.\"
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.Dd August 18, 2016
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.Dt CONNECT 2
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.Os
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.Sh NAME
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.Nm connect
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.Nd initiate a connection on a socket
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.Sh LIBRARY
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.Lb libc
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.Sh SYNOPSIS
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.In sys/socket.h
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.Ft int
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.Fn connect "int s" "const struct sockaddr *name" "socklen_t namelen"
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.Sh DESCRIPTION
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The
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.Fa s
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argument
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is a socket.
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If it is of type
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.Dv SOCK_DGRAM ,
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this call specifies the peer with which the socket is to be associated;
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this address is that to which datagrams are to be sent,
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and the only address from which datagrams are to be received.
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If the socket is of type
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.Dv SOCK_STREAM ,
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this call attempts to make a connection to
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another socket.
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The other socket is specified by
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.Fa name ,
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which is an address in the communications space of the socket.
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.Fa namelen
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indicates the amount of space pointed to by
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.Fa name ,
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in bytes; the
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.Fa sa_len
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member of
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.Fa name
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is ignored.
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Each communications space interprets the
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.Fa name
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argument in its own way.
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Generally, stream sockets may successfully
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.Fn connect
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only once; datagram sockets may use
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.Fn connect
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multiple times to change their association.
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Datagram sockets may dissolve the association
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by connecting to an invalid address, such as a null address.
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.Sh RETURN VALUES
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.Rv -std connect
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.Sh ERRORS
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The
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.Fn connect
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system call fails if:
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.Bl -tag -width Er
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.It Bq Er EBADF
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The
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.Fa s
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argument
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is not a valid descriptor.
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.It Bq Er EINVAL
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The
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.Fa namelen
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argument is not a valid length for the address family.
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.It Bq Er ENOTSOCK
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The
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.Fa s
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argument
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is a descriptor for a file, not a socket.
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.It Bq Er EADDRNOTAVAIL
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The specified address is not available on this machine.
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.It Bq Er EAFNOSUPPORT
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Addresses in the specified address family cannot be used with this socket.
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.It Bq Er EISCONN
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The socket is already connected.
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.It Bq Er ETIMEDOUT
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Connection establishment timed out without establishing a connection.
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.It Bq Er ECONNREFUSED
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The attempt to connect was forcefully rejected.
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.It Bq Er ECONNRESET
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The connection was reset by the remote host.
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.It Bq Er ENETUNREACH
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The network is not reachable from this host.
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.It Bq Er EHOSTUNREACH
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The remote host is not reachable from this host.
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.It Bq Er EADDRINUSE
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The address is already in use.
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.It Bq Er EFAULT
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The
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.Fa name
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argument specifies an area outside
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the process address space.
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.It Bq Er EINPROGRESS
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The socket is non-blocking
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and the connection cannot
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be completed immediately.
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It is possible to
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.Xr select 2
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for completion by selecting the socket for writing.
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.It Bq Er EINTR
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The connection attempt was interrupted by the delivery of a signal.
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The connection will be established in the background,
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as in the case of
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.Er EINPROGRESS .
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.It Bq Er EALREADY
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A previous connection attempt has not yet been completed.
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.It Bq Er EACCES
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An attempt is made to connect to a broadcast address (obtained through the
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.Dv INADDR_BROADCAST
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constant or the
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.Dv INADDR_NONE
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return value) through a socket that does not provide broadcast functionality.
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.It Bq Er EAGAIN
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An auto-assigned port number was requested but no auto-assigned ports
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are available.
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Increasing the port range specified by
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.Xr sysctl 3
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MIB variables
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.Va net.inet.ip.portrange.first
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and
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.Va net.inet.ip.portrange.last
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may alleviate the problem.
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.El
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.Pp
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The following errors are specific to connecting names in the UNIX domain.
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These errors may not apply in future versions of the UNIX IPC domain.
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.Bl -tag -width Er
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.It Bq Er ENOTDIR
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A component of the path prefix is not a directory.
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.It Bq Er ENAMETOOLONG
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A component of a pathname exceeded 255 characters,
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or an entire path name exceeded 1023 characters.
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.It Bq Er ENOENT
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The named socket does not exist.
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.It Bq Er EACCES
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Search permission is denied for a component of the path prefix.
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.It Bq Er EACCES
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Write access to the named socket is denied.
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.It Bq Er ELOOP
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Too many symbolic links were encountered in translating the pathname.
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.It Bq Er EPERM
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Write access to the named socket is denied.
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.El
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.Sh SEE ALSO
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.Xr accept 2 ,
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.Xr getpeername 2 ,
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.Xr getsockname 2 ,
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.Xr select 2 ,
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.Xr socket 2 ,
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.Xr sysctl 3 ,
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.Xr sysctl 8
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.Sh HISTORY
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The
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.Fn connect
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system call appeared in
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.Bx 4.2 .
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