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diff --git a/docs/man/nng_recvmsg.adoc b/docs/man/nng_recvmsg.adoc new file mode 100644 index 00000000..03cc99b2 --- /dev/null +++ b/docs/man/nng_recvmsg.adoc @@ -0,0 +1,67 @@ += nng_recvmsg(3) +// +// 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_recvmsg - recv message + +== SYNOPSIS + +[source, c] +----------- +#include <nng/nng.h> + +int nng_recvmsg(nng_socket s, nng_msg **msgp, int flags); +----------- + +== DESCRIPTION + +The `nng_recvmsg()` receives a message on socket _s_, storing the +received message at the location pointed to by _msgp_. + +TIP: Using this function gives access to the message structure, and thus may +offer more functionality than the simpler <<nng_recv#,nng_recv(3)>> function. + +The _flags_ may contain the following value: + +`NNG_FLAG_NONBLOCK`:: + The function returns immediately, even if no message is available. Without + this flag, the function will wait until a message is received by the socket + _s_, or any configured timer expires. + +NOTE: The semantics of what receiving a message means vary from protocol to +protocol, so examination of the protocol documentation is encouraged. (For +example, with an <<nng_req#,nng_req(7)>> socket a message may only be received +after a request has been sent, and an <<nng_sub#,nng_sub(7)>> socket +may only receive messages corresponding to topics to which it has subscribed.) +Furthermore, some protocols may not support receiving data at all, such as +<<nng_pub#,nng_pub(7)>>. + +== RETURN VALUES + +This function returns 0 on success, and non-zero otherwise. + +== ERRORS + +`NNG_EAGAIN`:: The socket _s_ cannot accept data for sending. +`NNG_ECLOSED`:: The socket _s_ is not open. +`NNG_EINVAL`:: An invalid set of _flags_ was specified. +`NNG_ENOMEM`:: Insufficient memory is available. +`NNG_ENOTSUP`:: The protocol for socket _s_ does not support receiving. +`NNG_ESTATE`:: The socket _s_ cannot receive data in this state. + +== SEE ALSO + +<<nng_msg_free#,nng_msg_free(3)>>, +<<nng_recv#,nng_recv(3)>>, +<<nng_sendmsg#,nng_sendmsg(3)>>, +<<nng_strerror#,nng_strerror(3)>>, +<<nng#,nng(7)>> |
