ZMQ_TCP
Section: 0MQ Manual (7)
Updated: 11/23/2012
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NAME
zmq_tcp - 0MQ unicast transport using TCPSYNOPSIS
TCP is an ubiquitous, reliable, unicast transport. When connecting distributed applications over a network with 0MQ, using the TCP transport will likely be your first choice.
ADDRESSING
A 0MQ endpoint is a string consisting of a transport:// followed by an address. The transport specifies the underlying protocol to use. The address specifies the transport-specific address to connect to.
For the TCP transport, the transport is tcp, and the meaning of the address part is defined below.
Assigning a local address to a socket
When assigning a local address to a socket using zmq_bind() with the tcp transport, the endpoint shall be interpreted as an interface followed by a colon and the TCP port number to use.
An interface may be specified by either of the following:
- • The wild-card *, meaning all available interfaces.
- • The primary IPv4 or IPv6 address assigned to the interface, in its numeric representation.
- • The non-portable interface name as defined by the operating system.
The TCP port number may be specified by:
- • A numeric value, usually above 1024 on POSIX systems.
- • The wild-card *, meaning a system-assigned ephemeral port.
When using ephemeral ports, the caller should retrieve the actual assigned port using the ZMQ_LAST_ENDPOINT socket option. See zmq_getsockopt(3) for details.
Connecting a socket
When connecting a socket to a peer address using zmq_connect() with the tcp transport, the endpoint shall be interpreted as a peer address followed by a colon and the TCP port number to use.
A peer address may be specified by either of the following:
- • The DNS name of the peer.
- • The IPv4 or IPv6 address of the peer, in its numeric representation.
EXAMPLES
Assigning a local address to a socket.
-
// TCP port 5555 on all available interfaces rc = zmq_bind(socket, "tcp:/// :5555"); assert (rc == 0); // TCP port 5555 on the local loop-back interface on all platforms rc = zmq_bind(socket, "tcp://127.0.0.1:5555"); assert (rc == 0); // TCP port 5555 on the first Ethernet network interface on Linux rc = zmq_bind(socket, "tcp://eth0:5555"); assert (rc == 0);
Connecting a socket.
-
// Connecting using an IP address rc = zmq_connect(socket, "tcp://192.168.1.1:5555"); assert (rc == 0); // Connecting using a DNS name rc = zmq_connect(socket, "tcp://server1:5555"); assert (rc == 0);
SEE ALSO
zmq_bind(3) zmq_connect(3) zmq_pgm(7) zmq_ipc(7) zmq_inproc(7) zmq(7)
AUTHORS
This 0MQ manual page was written by Pieter Hintjens <m[blue]ph@imatix.comm[][1]>, Martin Sustrik <m[blue]sustrik@250bpm.comm[][2]> and Martin Lucina <m[blue]mato@kotelna.skm[][3]>.
NOTES
- 1.
-
ph@imatix.com
- mailto:ph@imatix.com
- 2.
-
sustrik@250bpm.com
- mailto:sustrik@250bpm.com
- 3.
-
mato@kotelna.sk
- mailto:mato@kotelna.sk
Index
- NAME
- SYNOPSIS
- ADDRESSING
-
- Assigning a local address to a socket
- Connecting a socket
- EXAMPLES
- SEE ALSO
- AUTHORS
- NOTES