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diff --git a/docs/man/nng_rep.adoc b/docs/man/nng_rep.adoc new file mode 100644 index 00000000..dcc7e6fb --- /dev/null +++ b/docs/man/nng_rep.adoc @@ -0,0 +1,83 @@ += nng_rep(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_rep - reply protocol + +SYNOPSIS +-------- + +[source,c] +---------- +#include <nng/protocol/reqrep0/rep.h> + +int nng_rep0_open(nng_socket *s); +---------- + +DESCRIPTION +----------- + +The _nng_rep_ protocol is one half of a request/reply pattern. +In this pattern, a requester sends a message to one replier, who +is expected to reply. The request is resent if no reply arrives, +until a reply is received or the request times out. + +TIP: This protocol is useful in setting up RPC-like services. It +is also "reliable", in that a the requester will keep retrying until +a reply is received. + +The _nng_rep_ protocol is the replier side, and the +<<nng_req#,nng_req(7)>> protocol is the requester side. + +Socket Operations +~~~~~~~~~~~~~~~~~ + +The `nng_rep0_open()` call creates a requester socket. This socket +may be used to receive messages (requests), and then to send replies. Generally +a reply can only be sent after receiving a request. (Attempts to receive +a message will result in `NNG_ESTATE` if there is no outstanding request.) + +Attempts to send on a socket with no outstanding requests will result +in `NNG_ESTATE`. + +Raw mode sockets (set with `NNG_OPT_RAW`) ignore all these restrictions. + +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_MAXTTL`:: + + Maximum time-to-live. This option is an integer value + between 0 and 255, + inclusive, and is the maximum number of "hops" that a message may + pass through until it is discarded. The default value is 8. A value + of 0 may be used to disable the loop protection, allowing an infinite + number of hops. + +Protocol Headers +~~~~~~~~~~~~~~~~ + +The _nng_rep_ protocol uses a _backtrace_ in the header. This is +more fully documented in the <<nng_req#,nng_req(7)>> manual. + +SEE ALSO +-------- +<<nng#,nng(7)>>, +<<nng_req#,nng_req(7)>> |
