Sockets in Pascal - sockets

Question

How do you use network sockets in Pascal?
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Answer 1

Here's an example taken from http://www.bastisoft.de/programmierung/pascal/pasinet.html
program daytime;
{ Simple client program }
uses
sockets, inetaux, myerror;
const
RemotePort : Word = 13;
var
Sock : LongInt;
sAddr : TInetSockAddr;
sin, sout : Text;
Line : String;
begin
if ParamCount = 0 then GenError('Supply IP address as parameter.');
with sAddr do
begin
Family := af_inet;
Port := htons(RemotePort);
Addr := StrToAddr(ParamStr(1));
if Addr = 0 then GenError('Not a valid IP address.');
end;
Sock := Socket(af_inet, sock_stream, 0);
if Sock = -1 then SockError('Socket: ');
if not Connect(Sock, sAddr, sizeof(sAddr)) then SockError('Connect: ');
Sock2Text(Sock, sin, sout);
Reset(sin);
Rewrite(sout);
while not eof(sin) do
begin
Readln(sin, Line);
Writeln(Line);
end;
Close(sin);
Close(sout);
Shutdown(Sock, 2);
end.

Answer 2

If you're using FPC or Lazarus(which is basically a rad IDE for FPC and a clone of delphi) you could use the Synapse socket library. It's amazing.

Answer 3

If you are using Delphi, I highly recommend Indy sockets, a set of classes for easy manipulation of sockets and many other internet protocols (HTTP, FTP, NTP, POP3 etc.)

Answer 4

You cannot use OpenSSL with Indy version 10.5 that shippes with Delphi 2007. You have to download version 10,6 from http://www.indyproject.org/ and install it into the IDE.
Note that other packages might use Indy, like RemObjects, and therefore they have to be re-compiled too and this can be tricky due to cross-references.