blob: b66d694ce22d1637150a44bde4228e5ca527ef6d (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
|
= reqrep
This is a very simple RPC service using the REQ/REP method.
It is derived in part from Tim Dysinger's
http://nanomsg.org/gettingstarted/[Getting Started With Nanomsg]
examples, but we have updated for _nng_, and converted to use binary
frames across the wire instead of string data.
The protocol is simple:
* Client will send a 64-bit command (network byte order, i.e. big endian).
* Server sends a 64-bit response (also network byte order.)
The only command is "DATE", which has value 0x1. The value returned is
a UNIX timestamp (seconds since Jan 1, 1970.)
(We used 64-bit values for simplicity, and to avoid the Y2038 bug when
compiled on 64-bit systems.)
== Compiling
The following is an example typical of UNIX and similar systems like
Linux and macOS:
[source, bash]
----
% export CPPFLAGS="-I /usr/local/include"
% export LDFLAGS="-L /usr/local/lib -lnng"
% export CC="cc"
% ${CC} ${CPPFLAGS} reqrep.c -o reqrep ${LDFLAGS}
----
== Running
You can run either the client or the server, and use whatever legal
_nng_ URL you like:
[source, bash]
----
% ./reqrep server tcp://127.0.0.1:8899 &
% ./reqrep client tcp://127.0.0.1:8899
CLIENT: SENDING DATE REQUEST
SERVER: RECEIVED DATE REQUEST
SERVER: SENDING DATE: Thu Feb 8 10:26:18 2018
CLIENT: RECEIVED DATE: Thu Feb 8 10:26:18 2018
----
|
