SYNOPSIS

int zmq_connect (void *socket, const char *endpoint);

DESCRIPTION

The zmq_connect() function shall connect the socket referenced by the socket argument to the endpoint specified by the endpoint argument.

The endpoint argument is a string consisting of two parts as follows: transport://address. The transport part specifies the underlying transport protocol to use. The meaning of the address part is specific to the underlying transport protocol selected.

The following transports are defined:

inproc

local in-process (inter-thread) communication transport, see zmq_inproc(7)

ipc

local inter-process communication transport, see zmq_ipc(7)

tcp

unicast transport using TCP, see zmq_tcp(7)

pgm, epgm

reliable multicast transport using PGM, see zmq_pgm(7)

ZeroMQ sockets support one-to-many and many-to-one semantics. With the exception of ZMQ_PAIR sockets every ZeroMQ socket type supports being bound with zmq_bind() as a singular endpoint or connecting with zmq_connect() as one of many endpoints. This allows combinations such as 1 ZMQ_REP to 100 ZMQ_REP and 100 ZMQ_REQ to 1 ZMQ_REP socket connections. Refer to zmq_socket(3) for a description of the exact semantics involved when connecting or binding a socket to multiple endpoints.

Note
The connection will not be performed immediately but as needed by ØMQ. Thus a successful invocation of zmq_connect() does not indicate that a physical connection was or can actually be established. Because of this, for most socket types the order in which a listening socket is bound and a connecting socket is connected does not matter. However, for inproc:// scheme sockets, the zmq_bind() must be executed before any sockets zmq_connect() to that endpoint. Refer to zmq_inproc(7) for more details.

RETURN VALUE

The zmq_connect() function shall return zero if successful. Otherwise it shall return -1 and set errno to one of the values defined below.

ERRORS

EINVAL

The endpoint supplied is invalid.

EPROTONOSUPPORT

The requested transport protocol is not supported.

ENOCOMPATPROTO

The requested transport protocol is not compatible with the socket type.

ETERM

The ØMQ context associated with the specified socket was terminated.

ENOTSOCK

The provided socket was invalid.

EMTHREAD

No I/O thread is available to accomplish the task.

EXAMPLE

Connecting a subscriber socket to an in-process and a TCP transport
/* Create a ZMQ_SUB socket */
void *socket = zmq_socket (context, ZMQ_SUB);
assert (socket);
/* Connect it to an in-process transport with the address 'my_publisher' */
int rc = zmq_connect (socket, "inproc://my_publisher");
assert (rc == 0);
/* Connect it to the host server001, port 5555 using a TCP transport */
rc = zmq_connect (socket, "tcp://server001:5555");
assert (rc == 0);

SEE ALSO

AUTHORS

This ØMQ manual page was written by Martin Sustrik <sustrik@250bpm.com> and Martin Lucina <mato@kotelna.sk>.