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connect(2)

NAME

     connect -- initiate a connection on a socket

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <sys/types.h>
     #include <sys/socket.h>

     int
     connect(int s, const struct sockaddr *name, socklen_t namelen);

DESCRIPTION

     The s argument is a socket.  If it is of type SOCK_DGRAM, this call spec-
     ifies 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 SOCK_STREAM, this
     call attempts to make a connection to another socket.  The other socket
     is specified by name, which is an address in the communications space of
     the socket.  Each communications space interprets the name argument in
     its own way.  Generally, stream sockets may successfully connect() only
     once; datagram sockets may use connect() multiple times to change their
     association.  Datagram sockets may dissolve the association by connecting
     to an invalid address, such as a null address.

RETURN VALUES

     The connect() function returns the value 0 if successful; otherwise the
     value -1 is returned and the global variable errno is set to indicate the
     error.

ERRORS

     The connect() system call fails if:

     [EBADF]		The s argument is not a valid descriptor.

     [ENOTSOCK] 	The s argument is a descriptor for a file, not a
			socket.

     [EADDRNOTAVAIL]	The specified address is not available on this
			machine.

     [EAFNOSUPPORT]	Addresses in the specified address family cannot be
			used with this socket.

     [EISCONN]		The socket is already connected.

     [ETIMEDOUT]	Connection establishment timed out without establish-
			ing a connection.

     [ECONNREFUSED]	The attempt to connect was forcefully rejected.

     [ENETUNREACH]	The network is not reachable from this host.

     [EHOSTUNREACH]	The remote host is not reachable from this host.

     [EADDRINUSE]	The address is already in use.
     [EINTR]		The connection attempt was interrupted by the delivery
			of a signal.  The connection will be established in
			the background, as in the case of EINPROGRESS.

     [EALREADY] 	A previous connection attempt has not yet been com-
			pleted.

     [EACCES]		An attempt is made to connect to a broadcast address
			(obtained through the INADDR_BROADCAST constant or the
			INADDR_NONE return value) through a socket that does
			not provide broadcast functionality.

     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.

     [ENOTDIR]		A component of the path prefix is not a directory.

     [ENAMETOOLONG]	A component of a pathname exceeded 255 characters, or
			an entire path name exceeded 1023 characters.

     [ENOENT]		The named socket does not exist.

     [EACCES]		Search permission is denied for a component of the
			path prefix.

     [EACCES]		Write access to the named socket is denied.

     [ELOOP]		Too many symbolic links were encountered in translat-
			ing the pathname.

SEE ALSO

     accept(2), getpeername(2), getsockname(2), select(2), socket(2)

HISTORY

     The connect() system call appeared in 4.2BSD.

FreeBSD 5.4			 June 4, 1993			   FreeBSD 5.4

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