Exploring the select Io Model

Wsadata wsdata;
If (wsastartup (makeword (2, 2), & wsdata ))
{
Trace ("initialization failed ");

}

Socket sersock = socket (af_inet, sock_stream, 0 );
If (sersock = socket_error)
{

Trace ("failed to create socket ");
Wsacleanup ();
}

Sockaddr_in ADDR;
ADDR. sin_family = af_inet;
ADDR. sin_port = htons (5005 );
ADDR. sin_addr.s_un.s_addr = inet_addr ("127.0.0.1 ");

If (BIND (sersock, (sockaddr *) & ADDR, sizeof (ADDR) = socket_error)
{
Trace ("failed to create socket ");
Wsacleanup ();
}

If (Listen (sersock, 5) = socket_error)
{
Trace ("socket listener failed ");
Wsacleanup ();
}

Socket clisock;
Sockaddr_in cliaddr;

Int Len = sizeof (cliaddr );
Char Buf [maxbulen];
G_bready = true;

Fd_set fd_read;
Fd_zero (& fd_read );

Timeval TV;
TV. TV _sec = 2;
TV. TV _usec = 0;
Int res;
While (1)
{
Fd_set (sersock, & fd_read); // Add the listening socket to the readable model.
// G_itotalcli + = 1;

// Add link detection to delete the disconnected socket

 

For (INT I = 0; I <g_itotalcli; I ++)
{
Fd_set (g_clisocketarr [I], & fd_read );
}

Res = select (null, & fd_read, null, null, & TV );
Trace ("select called, Return Value % d \ n", Res );
If (RES = 0)
{
Continue; // timeout
}

If (fd_isset (sersock, & fd_read ))
{
Trace ("new connections are coming! \ N ");
Clisock = accept (sersock, (sockaddr *) & cliaddr, & Len );
G_clisocketarr [g_itotalcli ++] = clisock; // accepts the connection.
}

For (INT I = 0; I <g_itotalcli; I ++)
{
If (fd_isset (g_clisocketarr [I], & fd_read ))
{
Memset (BUF, 0, maxbulen );
Int recvres = Recv (g_clisocketarr [I], Buf, maxbulen, 0 );
If (recvres = 0 | (RES = socket_error & wsagetlasterror () = wsaeconnreset ))
{
Trace ("socket closed! \ N ");
Closesocket (g_clisocketarr [I]);
If (I <g_itotalcli-1)
{
G_clisocketarr [I --] = g_clisocketarr [-- g_itotalcli];
}
}
Else
{
Buf [recvres] = '\ 0 ';
Trace ("received message: % s \ n", Buf );
}
}
}
}
Return 0;