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diff --git a/docs/tutorials/014/page05.html b/docs/tutorials/014/page05.html deleted file mode 100644 index ca647ed5e20..00000000000 --- a/docs/tutorials/014/page05.html +++ /dev/null @@ -1,208 +0,0 @@ -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="Author" CONTENT="Bob McWhirter"> - <TITLE>ACE Tutorial 014</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 014</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>ACE_Stream Tutorial, Of Sorts</FONT></B></CENTER> - -<P> -<HR WIDTH="100%"> -<P> -Now we come to main(). In the previous task-chain tutorial - every thread pool had to have the same number of threads. This - time around, we leverage the construction method of ACE_Stream - and ACE_Module to customize the thread-pool size in each - ACE_Task of the stream. -<P> -Remember EndTask from the previous page? We create one here and push - it into the stream to take care of cleaning up the messages. - Technically, we could have replaced the default Tail task - created by the ACE framework but it seems to make more sense to - just push our "tail" onto the stream like the other tasks. The - caveat to this method is that you must be sure you don't push() - any other Modules behind the EndTask! -<P> -Once the stream of modules containing tasks is all setup then we can - put() some data into the stream for processing. The clever use - of Task::close() makes shutting downt the stream easier than - ever. No messing with hangup messages at the application level, - just close() when you're done! What could be simpler? -<P> -<HR WIDTH="100%"> -<PRE> - -<font color=red>// $Id$</font> - -<font color=red>// stream.cxx</font> -<font color=red>//</font> -<font color=red>// Tutorial regarding a way to use ACE_Stream.</font> -<font color=red>//</font> -<font color=red>// written by bob mcwhirter (bob@netwrench.com)</font> -<font color=red>//</font> -<font color=red>//</font> - -<font color=blue>#include</font> "<font color=green>Task.h</font>" -<font color=blue>#include</font> "<font color=green>EndTask.h</font>" -<font color=red>// This is our specialized ACE_Task.</font> - -<font color=blue>#include</font> <ace/Module.h> -<font color=blue>#include</font> <ace/Stream.h> -<font color=blue>#include</font> <ace/streams.h> -<font color=red>// These are the neccessary ACE headers.</font> - - -typedef ACE_Module<ACE_MT_SYNCH> Module; -typedef ACE_Stream<ACE_MT_SYNCH> Stream; -<font color=red>// Just to avoid a lot of typing, typedefs</font> -<font color=red>// are generally a good idea.</font> - -int main(int argc, char *argv[]) -{ - int numberOfMessages = argc > 1 ? <font color=#008888>ACE_OS::atoi</font>(argv[1]) : 3; - <font color=red>// unless otherwise specified, just send three messages</font> - <font color=red>// down the stream.</font> - - Stream theStream; - <font color=red>// the ACE_Stream itself.</font> - - <font color=red>// Now, we instantiate 4 different Tasks. These do not</font> - <font color=red>// need to be all the same class, but they do need to</font> - <font color=red>// all derrive from the same flavor of ACE_Task.</font> - <font color=red>//</font> - <font color=red>// Also, we instantiate a fifth end-cap Task to clean</font> - <font color=red>// up Message_Blocks as they reach the end.</font> - - Task *taskOne; - Task *taskTwo; - Task *taskThree; - Task *taskFour; - Task *taskEnd; - - <font color=red>// Out Task's take two arguments: a name, and the number</font> - <font color=red>// of threads to dedicate to the task.</font> - - taskOne = new Task("<font color=green>Task No. 1</font>", 1); - taskTwo = new Task("<font color=green>Task No. 2</font>", 3); - taskThree = new Task("<font color=green>Task No. 3</font>", 7); - taskFour = new Task("<font color=green>Task No. 4</font>", 1); - - <font color=red>// Our EndTask only takes 1 argument, as it actually</font> - <font color=red>// doesn't spawn any threads for processing.</font> - - taskEnd = new EndTask("<font color=green>End Task</font>"); - - Module *moduleOne; - Module *moduleTwo; - Module *moduleThree; - Module *moduleFour; - Module *moduleEnd; - - <font color=red>// ACE_Stream accepts ACE_Modules, which are simply a pair of</font> - <font color=red>// ACE_Tasks. One is dedicated for writing, while the other</font> - <font color=red>// is dedicated to reading. Think of the writing side as</font> - <font color=red>// downstream, and the reading side as upstream.</font> - <font color=red>//</font> - <font color=red>// We're only working with a unidirection Stream today,</font> - <font color=red>// so we'll only actually install a Task into the write</font> - <font color=red>// side of the module, effectively downstream.</font> - - moduleOne = new Module("<font color=green>Module No. 1</font>", taskOne); - moduleTwo = new Module("<font color=green>Module No. 2</font>", taskTwo); - moduleThree = new Module("<font color=green>Module No. 3</font>", taskThree); - moduleFour = new Module("<font color=green>Module No. 4</font>", taskFour); - moduleEnd = new Module("<font color=green>Module End</font>", taskEnd); - - <font color=red>// Now we push the Modules onto the Stream.</font> - <font color=red>// Pushing adds the module to the head, or</font> - <font color=red>// otherwise prepends it to whatever modules</font> - <font color=red>// are already installed.</font> - - <font color=red>// So, you need to push() the modules on -backwards-</font> - <font color=red>// from our viewpoint.</font> - - if (theStream.push(moduleEnd) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green>push</font>"), -1); - } - - if (theStream.push(moduleFour) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green>push</font>"), -1); - } - - <font color=red>// As we push a Module onto the Stream, it gets opened.</font> - <font color=red>// When a Module open()s, it opens the Tasks that it contains.</font> - <font color=red>//</font> - <font color=red>// Since we cannot provide an argument to this embedded</font> - <font color=red>// call to open(), we supplied specified the number of</font> - <font color=red>// threads in the constructor of our Tasks.</font> - - if (theStream.push(moduleThree) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green>push</font>"), -1); - } - - if (theStream.push(moduleTwo) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green>push</font>"), -1); - } - - if (theStream.push(moduleOne) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green>push</font>"), -1); - } - - <font color=red>// Now that the Modules are open, the Tasks threads should</font> - <font color=red>// be launching and entering their svc() loop, so we send</font> - <font color=red>// some messages down the Stream.</font> - - int sent = 1; - - ACE_Message_Block *message; - - while (sent <= numberOfMessages) { - - <font color=red>// First, create ourselves a Message_Block.</font> - <font color=red>// see Tutorials 10-13 for more information</font> - <font color=red>// about Message_Blocks and Message_Queues.</font> - - message = new ACE_Message_Block(128); - - <font color=red>// Now, we grab the write-pointer from the Block,</font> - <font color=red>// and sprintf() our text into it.</font> - - <font color=#008888>ACE_OS::sprintf</font>(message->wr_ptr(), "<font color=green>Message No. %d</font>", sent); - - <font color=red>// All we have to do now is drop the Message_Block</font> - <font color=red>// into the Stream.</font> - - <font color=red>// It is always a good idea to duplicate() a Message_Block</font> - <font color=red>// when you put it into any Message_Queue, as then</font> - <font color=red>// you can always be allowed to release() your copy</font> - <font color=red>// without worry.</font> - - if (theStream.put(message->duplicate(), 0) == -1) { - ACE_ERROR_RETURN ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green>put</font>"), -1); - } - - message->release(); - ++sent; - } - - <font color=red>// Now that we've sent our Message_Blocks, close down</font> - <font color=red>// the Stream.</font> - <font color=red>//</font> - <font color=red>// The Stream will automagically delete the Modules and</font> - <font color=red>// the contained Tasks. We don't have to do that.</font> - <font color=red>//</font> - <font color=red>// This call will block (due to the way we've written our</font> - <font color=red>// Task class) until all Message_Blocks have cleared the</font> - <font color=red>// entire Stream, and all associated threads have exited.</font> - - theStream.close(); - - return 0; -} -</PRE> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] </CENTER> |