Zmonitor (3) Linux Manual Page

zmonitor – socket event monitor

Synopsis

//  Create new zmonitor actor instance to monitor a zsock_t socket:
//
//      zactor_t *monitor = zactor_new (zmonitor, mysocket);
//
//  Destroy zmonitor instance.
//
//      zactor_destroy (&monitor);
//
//  Enable verbose logging of commands and activity.
//
//      zstr_send (monitor, "VERBOSE");
//
//  Listen to monitor event type (zero or types, ending in NULL):
//      zstr_sendx (monitor, "LISTEN", type, ..., NULL);
//
//      Events:
//      CONNECTED
//      CONNECT_DELAYED
//      CONNECT_RETRIED
//      LISTENING
//      BIND_FAILED
//      ACCEPTED
//      ACCEPT_FAILED
//      CLOSED
//      CLOSE_FAILED
//      DISCONNECTED
//      MONITOR_STOPPED
//      ALL
//
//  Start monitor; after this, any further LISTEN commands are ignored.
//
//      zstr_send (monitor, "START");
//      zsock_wait (monitor);
//
//  Receive next monitor event:
//
//      zmsg_t *msg = zmsg_recv (monitor);
//
//  This is the zmonitor constructor as a zactor_fn; the argument can be
//  a zactor_t, zsock_t, or libzmq void * socket:
CZMQ_EXPORT void
zmonitor(zsock_t *pipe, void *sock);

//  Selftest
CZMQ_EXPORT void
zmonitor_test(bool verbose);

Description

The zmonitor actor provides an API for obtaining socket events such as connected, listen, disconnected, etc. Socket events are only available for sockets connecting or bound to ipc:// and tcp:// endpoints.

This class wraps the ZMQ socket monitor API, see zmq_socket_monitor for details. Works on all versions of libzmq from 3.2 onwards. This class replaces zproxy_v2, and is meant for applications that use the CZMQ v3 API (meaning, zsock).

Example

From zmonitor_test method.

zsock_t *client = zsock_new(ZMQ_DEALER);
assert(client);
zactor_t *clientmon = zactor_new(zmonitor, client);
assert(clientmon);
if (verbose)
    zstr_sendx(clientmon, "VERBOSE", NULL);
zstr_sendx(clientmon, "LISTEN", "LISTENING", "ACCEPTED", NULL);
zstr_sendx(clientmon, "START", NULL);
zsock_wait(clientmon);

zsock_t *server = zsock_new(ZMQ_DEALER);
assert(server);
zactor_t *servermon = zactor_new(zmonitor, server);
assert(servermon);
if (verbose)
    zstr_sendx(servermon, "VERBOSE", NULL);
zstr_sendx(servermon, "LISTEN", "CONNECTED", "DISCONNECTED", NULL);
zstr_sendx(servermon, "START", NULL);
zsock_wait(servermon);

//  Allow a brief time for the message to get there...
zmq_poll(NULL, 0, 200);

//  Check client is now listening
int port_nbr = zsock_bind(client, "tcp://127.0.0.1:*");
assert(port_nbr != -1);
s_assert_event(clientmon, "LISTENING");

//  Check server connected to client
zsock_connect(server, "tcp://127.0.0.1:%d", port_nbr);
s_assert_event(servermon, "CONNECTED");

//  Check client accepted connection
s_assert_event(clientmon, "ACCEPTED");

zactor_destroy(&clientmon);
zactor_destroy(&servermon);
zsock_destroy(&client);
zsock_destroy(&server);
#endif

Authors

The czmq manual was written by the authors in the AUTHORS file.

Resources

Main web site: m[blue]m[]

Report bugs to the email <m[blue]zeromq-dev [at] lists.zeromq.orgm[][1]>

Copyright

Copyright (c) 1991-2012 iMatix Corporation — http://www.imatix.com Copyright other contributors as noted in the AUTHORS file. This file is part of CZMQ, the high-level C binding for 0MQ: http://czmq.zeromq.org This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/. LICENSE included with the czmq distribution.

Notes

1.

zeromq-dev [at] lists.zeromq.org

mailto:zeromq-dev [at] lists.zeromq.org

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