Re: Sockets between D and C(++) app
On Wednesday, 2 April 2014 at 21:54:58 UTC, FreeSlave wrote:
It's only server. Maybe problem is on client side.
Yes, it is only a server which needs to answer back the client;
And there was the problem: I was not fetching the client's
address, and since UDP is an unconnected protocol, I couldn't
send it back with just send.
So what I had to do was to create a client address and pass it in
receiveFrom(), and then use sendTo(in data, in clientAddr). Once
this was fixed, the server was able to answer my client.
N.b. auto addr_client = new InternetAddress didn't seem to work,
like if InternetAddress wasn't right for the Address parameter. I
explicitely needed Address.
Here's the code:
module main;
import std.stdio;
import std.socket;
import std.string;
import std.conv;
int main()
{
auto s = new UdpSocket();
auto addr = new InternetAddress(127.0.0.1, );
s.setOption(SocketOptionLevel.IP, SocketOption.REUSEADDR, true);
s.bind(addr);
Address addr_client = new InternetAddress();
while (true)
{
ubyte[2048] recv_buf;
immutable count = s.receiveFrom(recv_buf, addr_client);
char[] test = cast(char[])(recv_buf[0..count-1]); // -1 pour
compatibilité avec C string...
writefln(Received: %s\n, test);
auto rep = toStringz(Hello);
s.sendTo(rep[0..6], addr_client);
}
return 0;
}
Thanks all for your help, much appreciated!
Alexandre
Re: Sockets between D and C(++) app
It's only server. Maybe problem is on client side.
Try this if you are on Linux:
//Linux C client
#include sys/socket.h
#include sys/types.h
#include netinet/in.h
#include arpa/inet.h
#include stddef.h
#include string.h
#include stdio.h
int main()
{
int sock, res;
struct sockaddr_in addr;
const char* hello;
size_t len;
sock = socket(AF_INET, SOCK_DGRAM, 0);
if (sock 0)
{
printf(Can't create socket\n);
return -1;
}
addr.sin_family = AF_INET;
addr.sin_port = htons(5432);
addr.sin_addr.s_addr = inet_addr(127.0.0.1);
hello = Hello from C;
len = strlen(hello);
while (1)
{
res = sendto(sock, hello, len, 0, (struct
sockaddr*)addr, sizeof(addr));
if (res = 0)
{
printf(Can't send\n);
return -1;
}
}
close(sock);
return 0;
}
//D server
import std.socket;
import std.stdio;
int main(string[] args)
{
auto s = new UdpSocket(AddressFamily.INET);
auto addr = new InternetAddress(127.0.0.1, 5432);
s.setOption(SocketOptionLevel.IP, SocketOption.REUSEADDR,
true);
s.bind(addr);
while (true)
{
ubyte[2048] recv_buf;
int count = s.receiveFrom(recv_buf[]);
char[] test = cast(char[])recv_buf;
writefln(Received: %s\n, test);
}
return 0;
}
Note that you don't need to remove zero-symbol if you don't pass
it from client.
Re: Sockets between D and C(++) app
Alexandre L.:
Some comments on your code:
Here's my 'server' code:
int main(string[] args)
{
If you don't need args, then I suggest to not put it as main
argument. So probably this is better (note no int nor return, in
D they are not needed):
void main() {
...
}
int count = s.receiveFrom(recv_buf);
It's better to use immutable here, and infer the type (use
const/immutable everywhere you don't really need to mutate a
variable/argument/field):
immutable count = s.receiveFrom(recv_buf);
char[] test = cast(char[])recv_buf[0..count-1]; // -1 for C
string comp.
writefln(Received: %s\n, test);
char[] rep = regan\0.dup;
s.send(cast(ubyte[])rep);
casts are dangerous, because they silently assume you know what
you are doing. As first try I suggest you to remove every cast()
from your D program, and replace them with to!() or other
functions like toStringz. Sometimes this is not the most
efficient thing to do, but it's safer, so it's better when you
start to learn D.
Bye,
bearophile
Re: Sockets between D and C(++) app
On Wednesday, 2 April 2014 at 00:34:08 UTC, bearophile wrote: char[] rep = regan\0.dup; s.send(cast(ubyte[])rep); casts are dangerous, because they silently assume you know what you are doing. As first try I suggest you to remove every cast() from your D program, and replace them with to!() or other functions like toStringz. Sometimes this is not the most efficient thing to do, but it's safer, so it's better when you start to learn D. Bye, bearophile Thanks for your reply. As for cast, I seems not to have any option, because to! doesn't work as I would expect it. It would return me an array of numbers, instead of a string; So I kept the cast here, since I certainly know what it's doing -for now-. I generally use immutables, you caught me, here :-). As of main and return, I was not aware we could just ignore them if we didn't need them. I love explicit programming. However, I'm still stuck with toStringz(). Since it returns an immutable(char[]), I can't find how to pass it to Socket.send(), and I do not seem to be able to cast away the immutable :-s Alexandre
Re: Sockets between D and C(++) app
My bad; It returns immutable(char)*. Still won't work with send(); Am I right to supposed the receiving client must handle a ubyte[] as well (C++) ?
Re: Sockets and D?
Jimi_Hendrix wrote: Hi, I am new to D but not to programming. I have had some socket experience before. How would i connect to a server using sockets in D? A link to a D socket tutorial (if one exists) would also be appreciated. by the way, first post to a newsgroup for me As certain Tango users have neglected to tell you, Phobos also has a perfectly servicable socket interface in std.socket. If you know Sockets in C, you should have no problem with it. http://digitalmars.com/d/1.0/phobos/std_socket.html
Re: Sockets and D?
On Fri, 03 Apr 2009 04:19:10 +0400, Jimi_Hendrix myspo...@gmail.com wrote: Hi, I am new to D but not to programming. I have had some socket experience before. How would i connect to a server using sockets in D? A link to a D socket tutorial (if one exists) would also be appreciated. by the way, first post to a newsgroup for me Hi! I'd suggest you to look at Tango as it has very impressive networking feature set. Alternatively, you can use all those BSD sockets API functions from D directly (as you'd do in C/C++), but I wouldn't recommend going that low-lever.
Re: Sockets and D?
On Fri, 03 Apr 2009 04:35:21 +0400, Denis Koroskin wrote: I'd suggest you to look at Tango as it has very impressive networking feature set. tutorial? also what do i need to download to use tango?
Re: Sockets and D?
On Fri, 03 Apr 2009 04:55:59 +0400, jimi hendrix myspo...@gmail.com wrote: On Fri, 03 Apr 2009 04:35:21 +0400, Denis Koroskin wrote: I'd suggest you to look at Tango as it has very impressive networking feature set. tutorial? also what do i need to download to use tango? http://dsource.org/projects/tango http://dsource.org/projects/tango/wiki/Download http://dsource.org/projects/tango/wiki/Tutorials http://dsource.org/projects/tango/wiki/Examples Tango usually bundled with a compiler so that you get started faster.
