Provided by: libnng-dev_1.10.1-1_amd64 
NAME
nng_recvmsg - receive a message
SYNOPSIS
#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() 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 req socket a message may only be received
after a request has been sent, and an sub 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
pub.
RETURN VALUES
This function returns 0 on success, and non-zero otherwise.
ERRORS
NNG_EAGAIN
The operation would block, but NNG_FLAG_NONBLOCK was specified.
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.
NNG_ETIMEDOUT
The operation timed out.
SEE ALSO
nng_msg_free(3), nng_recv(3), nng_sendmsg(3), nng_strerror(3), nng_socket(5), nng(7) 2025-02-02 NNG_RECVMSG(3)