.\"
.\" @(#)connect.2 8.1 (Berkeley) 6/4/93
.\"
-.Dd June 4, 1993
+.Dd March 18, 2015
.Dt CONNECT 2
.Os BSD 4.2
.Sh NAME
.Fd #include <sys/types.h>
.Fd #include <sys/socket.h>
.Ft int
-.Fn connect "int s" "const struct sockaddr *name" "int namelen"
+.Fo connect
+.Fa "int socket"
+.Fa "const struct sockaddr *address"
+.Fa "socklen_t address_len"
+.Fc
.Sh DESCRIPTION
The parameter
-.Fa s
+.Fa socket
is a socket.
If it is of type
.Dv SOCK_DGRAM ,
this call attempts to make a connection to
another socket.
The other socket is specified by
-.Fa name ,
+.Fa address ,
which is an address in the communications space of the socket.
+.Pp
Each communications space interprets the
-.Fa name
+.Fa address
parameter in its own way.
Generally, stream sockets may successfully
.Fn connect
.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
+by calling
+.Xr disconnectx 2 ,
+or by connecting to an invalid address, such as a null address
or an address with
-the address family set to AF_UNPSEC (the error
-EAFNOSUPPORT will be harmlessly returned).
+the address family set to
+.Dv AF_UNSPEC
+(the error
+.Dv EAFNOSUPPORT
+will be harmlessly returned).
.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 .
+Upon successful completion, a value of 0 is returned.
+Otherwise, a value of -1 is returned and the global integer variable
+.Va errno
+is set to indicate the error.
.Sh ERRORS
The
.Fn connect
-call fails if:
+system call will fail if:
.Bl -tag -width Er
-.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 EACCES
+The destination address is a broadcast address and the
+socket option
+.Dv SO_BROADCAST
+is not set.
+.\" ==========
+.It Bq Er EADDRINUSE
+The address is already in use.
+.\" ==========
.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 EALREADY
+The socket is non-blocking
+and a previous connection attempt
+has not yet been completed.
+.\" ==========
+.It Bq Er EBADF
+.Fa socket
+is not a valid descriptor.
+.\" ==========
.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.
+The attempt to connect was ignored
+(because the target is not listening for connections)
+or explicitly rejected.
+.\" ==========
.It Bq Er EFAULT
The
-.Fa name
+.Fa address
parameter specifies an area outside
the process address space.
+.\" ==========
+.It Bq Er EHOSTUNREACH
+The target host cannot be reached (e.g., down, disconnected).
+.\" ==========
.It Bq Er EINPROGRESS
The socket is non-blocking
and the connection cannot
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.
+.\" ==========
+.It Bq Er EINTR
+Its execution was interrupted by a signal.
+.\" ==========
+.It Bq Er EINVAL
+An invalid argument was detected
+(e.g.,
+.Fa address_len
+is not valid for the address family,
+the specified address family is invalid).
+.\" ==========
+.It Bq Er EISCONN
+The socket is already connected.
+.\" ==========
+.It Bq Er ENETDOWN
+The local network interface is not functioning.
+.\" ==========
+.It Bq Er ENETUNREACH
+The network isn't reachable from this host.
+.\" ==========
+.It Bq Er ENOBUFS
+The system call was unable to allocate a needed memory buffer.
+.\" ==========
+.It Bq Er ENOTSOCK
+.Fa socket
+is not a file descriptor for a socket.
+.\" ==========
+.It Bq Er EOPNOTSUPP
+Because
+.Fa socket
+is listening, no connection is allowed.
+.\" ==========
+.It Bq Er EPROTOTYPE
+.Fa address
+has a different type than the socket
+that is bound to the specified peer address.
+.\" ==========
+.It Bq Er ETIMEDOUT
+Connection establishment timed out without establishing a connection.
+.\" ==========
+.It Bq Er ECONNRESET
+Remote host reset the connection request.
.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 Er
-.It Bq Er ENOTDIR
-A component of the path prefix is not a directory.
+.\" ==========
+.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 EIO
+An I/O error occurred while reading from or writing to the file system.
+.\" ==========
+.It Bq Er ELOOP
+Too many symbolic links were encountered in translating the pathname.
+This is taken to be indicative of a looping symbolic link.
+.\" ==========
.It Bq Er ENAMETOOLONG
A component of a pathname exceeded
.Dv {NAME_MAX}
characters, or an entire path name exceeded
.Dv {PATH_MAX}
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.
+.\" ==========
+.It Bq Er ENOTDIR
+A component of the path prefix is not a directory.
.El
+.Sh LEGACY SYNOPSIS
+.Fd #include <sys/types.h>
+.Fd #include <sys/socket.h>
+.Pp
+The include file
+.In sys/types.h
+is necessary.
.Sh SEE ALSO
.Xr accept 2 ,
+.Xr connectx 2 ,
+.Xr disconnectx 2 ,
+.Xr getsockname 2 ,
.Xr select 2 ,
.Xr socket 2 ,
-.Xr getsockname 2
+.Xr compat 5
.Sh HISTORY
The
.Fn connect
projects / apple / xnu.git / blobdiff