connect(3XNET)					   X/Open Networking Services Library Functions 				    connect(3XNET)

NAME

       connect - connect a socket

SYNOPSIS

       cc [ flag ... ] file ... -lxnet [ library ... ]
       #include <sys/socket.h>

       int connect(int socket, const struct sockaddr *address, socklen_t address_len);

DESCRIPTION

       The connect() function requests a connection to be made on a socket.  The function takes the following arguments:

       socket	       Specifies the file descriptor associated with the socket.

       address	       Points  to  a  sockaddr	structure containing the peer address.	The length and format of the address depend on the address
		       family of the socket.

       address_len     Specifies the length of the sockaddr structure pointed to by the address argument.

       If the socket has not already been bound to a local address,  connect() will bind it to an address which, unless the socket's address  fam-
       ily  is AF_UNIX, is an unused local address.

       If  the initiating socket is not connection-mode, then connect() sets the socket's peer address, but no connection is made.  For SOCK_DGRAM
       sockets, the peer address identifies where all datagrams are sent on subsequent send(3XNET) calls, and limits the remote sender for  subse-
       quent recv(3XNET) calls.  If address is a null address for the protocol, the socket's peer address will be reset.

       If  the	initiating  socket  is	connection-mode, then connect() attempts to establish a connection to the address specified by the address
       argument.

       If the connection cannot be established immediately and O_NONBLOCK is not set for the file descriptor for the socket, connect() will  block
       for  up	to  an unspecified timeout interval until the connection is established.  If the timeout interval expires before the connection is
       established, connect() will fail and the connection attempt will be aborted.  If connect() is interrupted by a signal that is caught  while
       blocked	waiting to establish a connection, connect() will fail and set errno to EINTR, but the connection request will not be aborted, and
       the connection will be established asynchronously.

       If the connection cannot be established immediately and O_NONBLOCK is set for the file descriptor for the socket, connect() will  fail  and
       set errno to EINPROGRESS, but the connection request will not be aborted, and the connection will be established asynchronously. Subsequent
       calls to connect() for the same socket, before the connection is established, will fail and set errno to EALREADY.

       When the connection has been established asynchronously, select(3C) and poll(2) will indicate that the file descriptor for  the	socket	is
       ready for writing.

       The socket in use may require the process to have appropriate privileges to use the connect() function.

USAGE

       If connect() fails, the state of the socket is unspecified.  Portable applications should close the file descriptor and create a new socket
       before attempting to reconnect.

RETURN VALUES

       Upon successful completion, connect() returns 0.  Otherwise, -1 is returned and errno is set to indicate the error.

ERRORS

       The connect() function will fail if:

       EADDRNOTAVAIL	       The specified address is not available from the local machine.

       EAFNOSUPPORT	       The specified address is not a valid address for the address family of the specified socket.

       EALREADY 	       A connection request is already in progress for the specified socket.

       EBADF		       The socket argument is not a valid file descriptor.

       ECONNREFUSED	       The target address was not listening for connections or refused the connection request.

       EFAULT		       The address parameter can not be accessed.

       EINPROGRESS	       O_NONBLOCK is set for the file descriptor for the socket and the connection cannot be immediately established;  the
			       connection will be established asynchronously.

       EINTR		       The  attempt to establish a connection was interrupted by delivery of a signal that was caught; the connection will
			       be established asynchronously.

       EISCONN		       The specified socket is connection-mode and is already connected.

       ENETUNREACH	       No route to the network is present.

       ENOTSOCK 	       The socket argument does not refer to a socket.

       EPROTOTYPE	       The specified address has a different type than the socket bound to the specified peer address.

       ETIMEDOUT	       The attempt to connect timed out before a connection was made.

       If the address family of the socket is AF_UNIX, then connect() will fail if:

       EIO		       An I/O error occurred while reading from or writing to the file system.

       ELOOP		       Too many symbolic links were encountered in translating the pathname in address.

       ENAMETOOLONG	       A component of a pathname exceeded NAME_MAX characters, or an entire pathname exceeded PATH_MAX characters.

       ENOENT		       A component of the pathname does not name an existing file or the pathname is an empty string.

       ENOTDIR		       A component of the path prefix of the pathname in address is not a directory.

       The connect() function may fail if:

       EACCES		       Search permission is denied for a component of the path prefix; or write access to the named socket is denied.

       EADDRINUSE	       Attempt to establish a connection that uses addresses that are already in use.

       ECONNRESET	       Remote host reset the connection request.

       EHOSTUNREACH	       The destination host cannot be reached (probably because the host is down or a remote router cannot reach it).

       EINVAL		       The address_len argument is not a valid length for the address family; or invalid address family in sockaddr struc-
			       ture.

       ENAMETOOLONG	       Pathname resolution of a symbolic link produced an intermediate result whose length exceeds PATH_MAX.

       ENETDOWN 	       The local interface used to reach the destination is down.

       ENOBUFS		       No buffer space is available.

       ENOSR		       There were insufficient STREAMS resources available to complete the operation.

       EOPNOTSUPP	       The socket is listening and can not be connected.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       close(2),  poll(2), accept(3XNET), bind(3XNET), getsockname(3XNET), select(3C), send(3XNET), shutdown(3XNET), socket(3XNET), attributes(5),
       standards(5)

SunOS 5.10							    10 Jun 2002 						    connect(3XNET)