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diff --git a/docs/nng_sub.adoc b/docs/nng_sub.adoc deleted file mode 100644 index 579e4cf0..00000000 --- a/docs/nng_sub.adoc +++ /dev/null @@ -1,83 +0,0 @@ -= nng_sub(7) -// -// Copyright 2018 Staysail Systems, Inc. <info@staysail.tech> -// Copyright 2018 Capitar IT Group BV <info@capitar.com> -// -// This document is supplied under the terms of the MIT License, a -// copy of which should be located in the distribution where this -// file was obtained (LICENSE.txt). A copy of the license may also be -// found online at https://opensource.org/licenses/MIT. -// - -== NAME - -nng_sub - subscriber protocol - -== SYNOPSIS - -[source,c] ----------- -#include <nng/protocol/pubsub0/sub.h> - -int nng_sub0_open(nng_socket *s); ----------- - -== DESCRIPTION - -The _nng_sub_ protocol is one half of a publisher/subscriber pattern. -In this pattern, a publisher sends data, which is broadcast to all -subscribers. The subscribing applications only see the data to which -they have subscribed. - -The _nng_sub_ protocol is the subscriber side, and the -<<nng_pub#,nng_pub(7)>> protocol is the publisher side. - -NOTE: In this implementation, the publisher delivers all messages to all -subscribers. The subscribers maintain their own subscriptions, and filter -them locally. Thus, this pattern should not be used in an attempt to -reduce bandwidth consumption. - -The topics that subscribers subscribe to is just the first part of -the message body. Applications should construct their messages -accordingly. - -=== Socket Operations - -The `nng_sub0_open()` call creates a subscriber socket. This socket -may be used to receive messages, but is unable to send them. Attempts -to send messages will result in `NNG_ENOTSUP`. - -=== Protocol Versions - -Only version 0 of this protocol is supported. (At the time of writing, -no other versions of this protocol have been defined.) - -=== Protocol Options - -The following protocol-specific options are available. - -`NNG_OPT_SUB_SUBSCRIBE`:: - - This option registers a topic that the subscriber is interested in. - The option is write-only, and takes an array of bytes, of arbitrary size. - Each incoming message is checked against the list of subscribed topics. - If the body begins with the entire set of bytes in the topic, then the - message is accepted. If no topic matches, then the message is - discarded. -+ -TIP: To receive all messages, an empty topic (zero length) can be used. - -`NNG_OPT_SUB_UNSUBSCRIBE`:: - - This option, also read-only, removes a topic from the subscription list. - Note that if the topic was not previously subscribed to with - `NNG_OPT_SUB_SUBSCRIBE` then an `NNG_ENOENT` error will result. - -=== Protocol Headers - -The _nng_sub_ protocol has no protocol-specific headers. - -== SEE ALSO - -<<nng#,nng(7)>>, -<<nng_pub#,nng_pub(7)>> |