mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-23 11:18:54 +00:00
f70177e76e
Submitted by: John Birrel(L?) changes for threadsafe operations
172 lines
5.4 KiB
Groff
172 lines
5.4 KiB
Groff
.\" Copyright (c) 1983, 1993
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. All advertising materials mentioning features or use of this software
|
|
.\" must display the following acknowledgement:
|
|
.\" This product includes software developed by the University of
|
|
.\" California, Berkeley and its contributors.
|
|
.\" 4. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" @(#)connect.2 8.1 (Berkeley) 6/4/93
|
|
.\"
|
|
.Dd June 4, 1993
|
|
.Dt CONNECT 2
|
|
.Os BSD 4.2
|
|
.Sh NAME
|
|
.Nm connect
|
|
.Nd initiate a connection on a socket
|
|
.Sh SYNOPSIS
|
|
.Fd #include <sys/types.h>
|
|
.Fd #include <sys/socket.h>
|
|
.Ft int
|
|
.Fn connect "int s" "struct sockaddr *name" "int namelen"
|
|
.Sh DESCRIPTION
|
|
The parameter
|
|
.Fa s
|
|
is a socket.
|
|
If it is of type
|
|
.Dv SOCK_DGRAM ,
|
|
this call specifies the peer with which the socket is to be associated;
|
|
this address is that to which datagrams are to be sent,
|
|
and the only address from which datagrams are to be received.
|
|
If the socket is of type
|
|
.Dv SOCK_STREAM ,
|
|
this call attempts to make a connection to
|
|
another socket.
|
|
The other socket is specified by
|
|
.Fa name ,
|
|
which is an address in the communications space of the socket.
|
|
Each communications space interprets the
|
|
.Fa name
|
|
parameter in its own way.
|
|
Generally, stream sockets may successfully
|
|
.Fn connect
|
|
only once; datagram sockets may use
|
|
.Fn connect
|
|
multiple times to change their association.
|
|
Datagram sockets may dissolve the association
|
|
by connecting to an invalid address, such as a null address.
|
|
.Sh IMPLEMENTATION NOTES
|
|
.Pp
|
|
In the non-threaded library
|
|
.Fn connect
|
|
is implemented as the
|
|
.Va connect
|
|
syscall.
|
|
.Pp
|
|
In the threaded library, the
|
|
.Va connect
|
|
syscall is assembled to
|
|
.Fn _thread_sys_connect
|
|
and
|
|
.Fn connect
|
|
is implemented as a function which locks
|
|
.Va s
|
|
for read and write, then calls
|
|
.Fn _thread_sys_connect .
|
|
If the call to
|
|
.Fn _thread_sys_connect
|
|
would block, a context switch is performed. Before returning,
|
|
.Fn connect
|
|
unlocks
|
|
.Va s .
|
|
.Sh RETURN VALUES
|
|
If the connection or binding succeeds, 0 is returned.
|
|
Otherwise a -1 is returned, and a more specific error
|
|
code is stored in
|
|
.Va errno .
|
|
.Sh ERRORS
|
|
The
|
|
.Fn connect
|
|
call fails if:
|
|
.Bl -tag -width EADDRNOTAVAILABB
|
|
.It Bq Er EBADF
|
|
.Fa s
|
|
is not a valid descriptor.
|
|
.It Bq Er ENOTSOCK
|
|
.Fa s
|
|
is a descriptor for a file, not a socket.
|
|
.It Bq Er EADDRNOTAVAIL
|
|
The specified address is not available on this machine.
|
|
.It Bq Er EAFNOSUPPORT
|
|
Addresses in the specified address family cannot be used with this socket.
|
|
.It Bq Er EISCONN
|
|
The socket is already connected.
|
|
.It Bq Er ETIMEDOUT
|
|
Connection establishment timed out without establishing a connection.
|
|
.It Bq Er ECONNREFUSED
|
|
The attempt to connect was forcefully rejected.
|
|
.It Bq Er ENETUNREACH
|
|
The network isn't reachable from this host.
|
|
.It Bq Er EADDRINUSE
|
|
The address is already in use.
|
|
.It Bq Er EFAULT
|
|
The
|
|
.Fa name
|
|
parameter specifies an area outside
|
|
the process address space.
|
|
.It Bq Er EINPROGRESS
|
|
The socket is non-blocking
|
|
and the connection cannot
|
|
be completed immediately.
|
|
It is possible to
|
|
.Xr select 2
|
|
for completion by selecting the socket for writing.
|
|
.It Bq Er EALREADY
|
|
The socket is non-blocking
|
|
and a previous connection attempt
|
|
has not yet been completed.
|
|
.El
|
|
.Pp
|
|
The following errors are specific to connecting names in the UNIX domain.
|
|
These errors may not apply in future versions of the UNIX IPC domain.
|
|
.Bl -tag -width EADDRNOTAVAILABB
|
|
.It Bq Er ENOTDIR
|
|
A component of the path prefix is not a directory.
|
|
.It Bq Er EINVAL
|
|
The pathname contains a character with the high-order bit set.
|
|
.It Bq Er ENAMETOOLONG
|
|
A component of a pathname exceeded 255 characters,
|
|
or an entire path name exceeded 1023 characters.
|
|
.It Bq Er ENOENT
|
|
The named socket does not exist.
|
|
.It Bq Er EACCES
|
|
Search permission is denied for a component of the path prefix.
|
|
.It Bq Er EACCES
|
|
Write access to the named socket is denied.
|
|
.It Bq Er ELOOP
|
|
Too many symbolic links were encountered in translating the pathname.
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr accept 2 ,
|
|
.Xr select 2 ,
|
|
.Xr socket 2 ,
|
|
.Xr getsockname 2
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
function call appeared in
|
|
.Bx 4.2 .
|