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diff --git a/docs/tutorials/010/page02.html b/docs/tutorials/010/page02.html deleted file mode 100644 index 49beffefbd9..00000000000 --- a/docs/tutorials/010/page02.html +++ /dev/null @@ -1,125 +0,0 @@ -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="Author" CONTENT="James CE Johnson"> - <TITLE>ACE Tutorial 010</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 010</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Passing chunks of data through an ACE_Message_Queue</FONT></B></CENTER> - - -<P> -<HR WIDTH="100%"> - -We'll look first at <A HREF="message_queue.cpp">main()</A>. -<P> - -<HR WIDTH="100%"> -<PRE> -<font color=red>// $Id$</font> - -<font color=red>/* To illustrate the ACE_Message_Queue, we use a derivative of - ACE_Task<>. We also derive from ACE_Message_Block to show that we - don't have memory leaks. */</font> -<font color=blue>#include</font> "<font color=green>task.h</font>" -<font color=blue>#include</font> "<font color=green>block.h</font>" - -int -run_test (int iterations, - int threads) -{ - <font color=red>/* Create and start an instance of our Task object. */</font> - Task task (threads); - - if (task.open () == -1) - ACE_ERROR_RETURN ((LM_ERROR, - "<font color=green>%p\n</font>", - "<font color=green>open</font>"), - -1); - - <font color=red>/* Give the threads a moment to open. This isn't really necessary - but if we don't we find that all of our blocks are constructed and - enqueued before any of the threads get created. Basically, the - sleep() makes the output look more interesting. */</font> - <font color=#008888>ACE_OS::sleep</font> (ACE_Time_Value (1)); - - int i; - for (i = 0; i < iterations; ++i) - { - <font color=red>/* Create a new message block to hold our data. Here, we ask - for a block that has 128 bytes of data space. */</font> - Block *message; - ACE_NEW_RETURN (message, - Block (128), - -1); - - <font color=red>/* Grab the "<font color=green>write pointer</font>". This is a pointer into the data - area where we can write our data. After writting the data you - have to increment the wr_ptr() so that subsequent writes won't - clobber what you've put there. */</font> - <font color=#008888>ACE_OS::sprintf</font> (message->wr_ptr (), - "<font color=green>This is message %d.</font>", - i); - message->wr_ptr (<font color=#008888>ACE_OS::strlen</font> (message->rd_ptr ())); - - <font color=red>/* Put the message block into the queue. One of the threads in - the Task object will pick up the block and "<font color=green>do work</font>" on it. */</font> - if (task.putq (message) == -1) - break; - } - - <font color=red>/* Once we're done, we have to signal the Task objects to shut - down. There are several choices including: - Send a message of - zero length - Send a message with a special content I don't like - these choices because they're likely to interfere with application - logic. Instead, I use the message type feature to send a message - of type "<font color=green>hangup</font>". The default type is MB_DATA, so when the tasks - get a MB_HANGUP type, they know to go away. */</font> - Block *message; - - ACE_NEW_RETURN (message, - Block (), - -1); - message->msg_type (<font color=#008888>ACE_Message_Block::MB_HANGUP</font>); - task.putq (message); - - <font color=red>/* Wait for the threads in our task object to go away. */</font> - task.wait (); - - return 0; -} - -int -main (int argc, char *argv[]) -{ - <font color=red>/* Set the number of iterations through our putq() loop and the - number of threads to use in our Task<> derivative. */</font> - int iterations = argc > 1 ? atoi (argv[1]) : 9; - int threads = argc > 2 ? atoi (argv[2]) : 2; - - run_test (iterations, threads); - - ACE_DEBUG ((LM_DEBUG, - "<font color=green>(%P|%t) Application exiting\n</font>")); - - return 0; -} -</PRE> -<HR WIDTH="100%"> -<P> -This looks a lot like our thread-pool server and it even does some things -better. In particular, I've scoped the Task object so that it's destructor -will have a chance to get called before the application exits. -Notice how we write actual data into the message block though. In the thread-pool -server we just provided a pointer. Writting the data is actually a more correct -way of doing things since you don't get into strange pointer casting situations. -What if you want to put complex objects into the message block though? We'll do -that in the next tutorial, let's stick with the basics first. -<P> -On the next page we'll take a look at our Block object... -<P> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page03.html">Continue This Tutorial</A>]</CENTER> |