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diff --git a/docs/man/nng_sub.7.adoc b/docs/man/nng_sub.7.adoc deleted file mode 100644 index b362c656..00000000 --- a/docs/man/nng_sub.7.adoc +++ /dev/null @@ -1,99 +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/nng.h> -#include <nng/protocol/pubsub0/sub.h> ----- - -== DESCRIPTION - -(((protocol, _sub_))) -The ((_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 _sub_ protocol is the subscriber side, and the -xref:nng_pub.7.adoc[_pub_] 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 xref:nng_sub_open.3.adoc[`nng_sub0_open()`] functions create 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`))(((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. -+ -NOTE: This option is a byte array. Thus if you use -xref:nng_socket_set.3.adoc[`nng_socket_set_string()`] the `NUL` terminator byte will -be included in the topic. -If that isn't desired, consider using -xref:nng_socket_set.3.adoc[`nng_socket_set()`] and using `strlen()` of the topic -as the topic size. -+ -TIP: To receive all messages, an empty topic (zero length) can be used. - -((`NNG_OPT_SUB_UNSUBSCRIBE`)):: - - This option, also write-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. - -((`NNG_OPT_SUB_PREFNEW`)):: - - (`bool`) - This read/write option specifies the behavior of the subscriber when the queue is full. - When `true` (the default), the subscriber will make room in the queue by removing the oldest message. - When `false`, the subscriber will reject messages if the message queue does not have room. - -=== Protocol Headers - -The _sub_ protocol has no protocol-specific headers. - -== SEE ALSO - -[.text-left] -xref:nng_sub_open.3.adoc[nng_sub_open(3)], -xref:nng_pub.7.adoc[nng_pub(7)], -xref:nng.7.adoc[nng(7)] |