ACE Tutorial 015
Building a protocol stream
We'll take a look first at the client application. As usual, our goal
is to keep the main() application as simple as possible and
delegate the tricky stuff to another object.
// page02.html,v 1.14 1999/09/22 03:13:52 jcej Exp
/* The Client object will implement the nasty details of connecting to
communicating with the server
*/
#include "Client_i.h"
int main(int argc, char *argv[])
{
// How many messages will we send?
int mcount = argc > 1 ? ACE_OS::atoi(argv[1]) : 3;
// Construct a Client with our desired endpoint.
Client client(ACE_DEFAULT_SERVER_PORT,ACE_DEFAULT_SERVER_HOST);
// Attempt to open the connection to the server.
if( client.open() == -1 )
{
ACE_ERROR_RETURN ((LM_ERROR, "%p\n", "Client::open()"), -1);
}
// Send a few messages to the server and get some responses...
for( int i = 0 ; i < mcount ; ++i )
{
// Since we'll be using a Protocol Stream (even though we
// don't know that at this level) we require the use of
// ACE_Message_Block objects to send/receive data.
ACE_Message_Block * message = new ACE_Message_Block( 128 );
// Construct a silly message to send to the server.
// Notice that we're careful to add one to the strlen() so
// that we also send the end-of-string NULL character.
ACE_OS::sprintf (message->wr_ptr (), "This is message %d.", i);
message->wr_ptr (strlen (message->rd_ptr ())+1);
// client will take ownership of the message block so that
// we don't have to remember to release(). We *do* have
// to remember not to use it after put() since it may be
// released almost immediately.
client.put( message );
ACE_Message_Block * response;
// get() takes an ACE_Message_Block pointer reference. We then
// assume ownership of it and must release() when we're done.
if( client.get( response ) == -1 )
{
ACE_DEBUG ((LM_INFO, "(%P|%t) Failed to get response from server\n" ));
break;
}
ACE_DEBUG ((LM_INFO, "(%P|%t) The server's response: (%s)\n",
response->rd_ptr()));
// Now that we're through with the response we have to
// release() it to avoid memory leaks.
response->release();
}
ACE_DEBUG ((LM_INFO, "(%P|%t) Shutting down the stream\n" ));
// Before we exit, it's a good idea to properly close() the connection.
if( client.close() == -1 )
{
ACE_ERROR_RETURN ((LM_ERROR, "%p\n", "Client::close()"), -1);
}
return(0);
}
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