# zmq_inproc(7) Manual Page

## NAME

zmq_inproc - 0MQ local in-process (inter-thread) communication transport

## SYNOPSIS

The in-process transport passes messages via memory directly between threads sharing a single ØMQ context.

Note | No I/O threads are involved in passing messages using the inproc transport. Therefore, if you are using a ØMQ context for in-process messaging only you can initialise the context with zero I/O threads. See zmq_init(3) for details.

## ADDRESSING

A ØMQ 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 in-process transport, the transport is `inproc`, 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 inproc transport, the endpoint shall be interpreted as an arbitrary string identifying the name to create. The name must be unique within the ØMQ context associated with the socket and may be up to 256 characters in length. No other restrictions are placed on the format of the name.

### Connecting a socket

When connecting a socket to a peer address using zmq_connect() with the inproc transport, the endpoint shall be interpreted as an arbitrary string identifying the name to connect to. Before version 4.0 he name must have been previously created by assigning it to at least one socket within the same ØMQ context as the socket being connected. Since version 4.0 the order of zmq_bind() and zmq_connect() does not matter just like for the tcp transport type.

## EXAMPLES

Assigning a local address to a socket

    //  Assign the in-process name "#1"
    rc = zmq_bind(socket, "inproc://#1");
    assert (rc == 0);
    //  Assign the in-process name "my-endpoint"
    rc = zmq_bind(socket, "inproc://my-endpoint");
    assert (rc == 0);

Connecting a socket

    //  Connect to the in-process name "#1"
    rc = zmq_connect(socket, "inproc://#1");
    assert (rc == 0);
    //  Connect to the in-process name "my-endpoint"
    rc = zmq_connect(socket, "inproc://my-endpoint");
    assert (rc == 0);

## SEE ALSO

zmq_bind(3) zmq_connect(3) zmq_ipc(7) zmq_tcp(7) zmq_pgm(7) zmq_vmci(7) zmq(7)

## AUTHORS

This page was written by the ØMQ community. To make a change please read the ØMQ Contribution Policy at http://www.zeromq.org/docs:contributing.