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CONNECT(2)		    BSD	System Calls Manual		    CONNECT(2)

     connect --	initiate a connection on a socket

     Standard C	Library	(libc, -lc)

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

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

     The parameter s is	a socket.  If it is of type SOCK_DGRAM,	this call
     specifies the peer	with which the socket is to be associated; this	ad-
     dress 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 commu-
     nications space of	the socket.  Each communications space interprets the
     name parameter in its own way.  Generally,	stream sockets may success-
     fully connect() only once;	datagram sockets may use connect() multiple
     times to change their association.	 Datagram sockets may dissolve the as-
     sociation by connecting to	an invalid address, such as a null address.

     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

     The connect() call	fails if:

     [EBADF]		s is not a valid descriptor.

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

     [EADDRNOTAVAIL]	The specified address is not available on this ma-

     [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.

     [EFAULT]		The name parameter specifies an	area outside the
			process	address	space.

     [EINPROGRESS]	The socket is non-blocking and the connection cannot
			be completed immediately.  It is possible to select(2)
			for completion by selecting the	socket for writing.

     [EALREADY]		The socket is non-blocking and a previous connection
			attempt	has not	yet been completed.

     [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.

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

     The connect() function call appeared in 4.2BSD.

BSD				 June 4, 1993				   BSD


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