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diff --git a/docs/tutorials/017/page02.html b/docs/tutorials/017/page02.html deleted file mode 100644 index 81aeb9d0b8b..00000000000 --- a/docs/tutorials/017/page02.html +++ /dev/null @@ -1,195 +0,0 @@ -<!-- $Id$ --> -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="Author" CONTENT="James CE Johnson"> - <TITLE>ACE Tutorial 017</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 017</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Using the ACE_Barrier synch object</FONT></B></CENTER> - -<P> -<HR WIDTH="100%"> -First, lets take a look at the main() routine and how it will use the -Barrier wrapper class. A simple ACE_Task derivative is used so that -we can perform work in multiple threads. These threads will use the -barrier to synch in a couple of places. -<P> -Obviously this isn't a very realistic example but you should be able -to get the idea of how to use a Barrier without getting hung up in -application-level details. -<HR> -<PRE> - -<font color=red>// $Id$</font> - -<font color=blue>#include</font> "<font color=green>Barrier_i.h</font>" -<font color=blue>#include</font> "<A HREF="../../../ace/Task.h">ace/Task.h</A>" - -<font color=red>/* We'll use a simple Task<> derivative to test our new Barrier - object. -*/</font> -class Test : public ACE_Task<ACE_NULL_SYNCH> -{ -public: - - <font color=red>// Construct the object with a desired thread count</font> - Test(int _threads); - - <font color=red>// Open/begin the test. As usual, we have to match the</font> - <font color=red>// ACE_Task signature.</font> - int open(void * _unused = 0); - - <font color=red>// Change the threads_ value for the next invocation of open()</font> - void threads(int _threads); - - <font color=red>// Get the current threads_ value.</font> - int threads(void); - - <font color=red>// Perform the test</font> - int svc(void); - -protected: - <font color=red>// How many threads the barrier will test.</font> - int threads_; - - <font color=red>// The Barrier object we'll use in our tests below</font> - Barrier barrier_; -}; - -<font color=red>/* Construct the object & initialize the threads value for open() to - use. -*/</font> -<font color=#008888>Test::Test</font>(int _threads) - : threads_(_threads) -{ -} - -<font color=red>/* As usual, our open() will create one or more threads where we'll do - the interesting work. -*/</font> -int <font color=#008888>Test::open</font>(void * _unused) -{ - ACE_UNUSED_ARG(_unused); - - <font color=red>// One thing about the barrier: You have to tell it how many</font> - <font color=red>// threads it will be synching. The threads() mutator on my</font> - <font color=red>// Barrier class lets you do that and hides the implementation</font> - <font color=red>// details at the same time.</font> - barrier_.threads(threads_); - - <font color=red>// Activate the tasks as usual... Like the other cases where</font> - <font color=red>// we're joining (or waiting for) our threads, we can't use</font> - <font color=red>// THR_DETACHED.</font> - return this->activate(THR_NEW_LWP, threads_); -} - -void <font color=#008888>Test::threads</font>(int _threads) -{ - threads_ = _threads; -} - -int <font color=#008888>Test::threads</font>(void) -{ - return threads_; -} - -<font color=red>/* svc() will execute in each thread & do a few things with the - Barrier we have. - */</font> -int <font color=#008888>Test::svc</font>(void) -{ - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t|%T)\<font color=#008888>tTest::svc</font>() Entry\n</font>")); - - <font color=red>// Initialize the random number generator. We'll use this to</font> - <font color=red>// create sleep() times in each thread. This will help us see</font> - <font color=red>// if the barrier synch is working.</font> - ACE_Time_Value now(<font color=#008888>ACE_OS::gettimeofday</font>()); - ACE_RANDR_TYPE seed = now.usec(); - <font color=#008888>ACE_OS::srand</font>(seed); - int delay; - - <font color=red>// After saying hello above, sleep for a random amount of time</font> - <font color=red>// from 1 to 6 seconds. That will cause the next message</font> - <font color=red>// "<font color=green>Entering wait()</font>" to be staggered on the output as each</font> - <font color=red>// thread's sleep() returns.</font> - delay = <font color=#008888>ACE_OS::rand_r</font>(seed)%5; - <font color=#008888>ACE_OS::sleep</font>(abs(delay)+1); - - <font color=red>// When executing the app you should see these messages</font> - <font color=red>// staggered in an at-most 6 second window. That is, you</font> - <font color=red>// won't likely see them all at once.</font> - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t|%T)\<font color=#008888>tTest::svc</font>() Entering wait()\n</font>")); - - <font color=red>// All of the threads will now wait at this point. As each</font> - <font color=red>// thread finishes the sleep() above it will join the waiters.</font> - if( barrier_.wait() == -1 ) - { - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t|%T)\tbarrier_.wait() failed!\n</font>")); - return 0; - } - - <font color=red>// When all threads have reached wait() they will give us this</font> - <font color=red>// message. If you execute this, you should see all of the</font> - <font color=red>// "<font color=green>Everybody together</font>" messages at about the same time.</font> - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t|%T)\<font color=#008888>tTest::svc</font>() Everybody together?\n</font>")); - - <font color=red>// Now we do the sleep() cycle again...</font> - delay = <font color=#008888>ACE_OS::rand_r</font>(seed)%5; - <font color=#008888>ACE_OS::sleep</font>(abs(delay)+1); - - <font color=red>// As before, these will trickle in over a few seconds.</font> - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t|%T)\<font color=#008888>tTest::svc</font>() Entering done()\n</font>")); - - <font color=red>// This time we call done() instead of wait(). done()</font> - <font color=red>// actually invokes wait() but before returning here, it will</font> - <font color=red>// clean up a few resources. The goal is to prevent carrying</font> - <font color=red>// around objects you don't need.</font> - if( barrier_.done() == -1 ) - { - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t|%T)\tbarrier_.done() failed!\n</font>")); - return 0; - } - - <font color=red>// Since done() invokes wait() internally, we'll see this</font> - <font color=red>// message from each thread simultaneously</font> - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t|%T)\<font color=#008888>tTest::svc</font>() Is everyone still here?\n</font>")); - - <font color=red>// A final sleep()</font> - delay = <font color=#008888>ACE_OS::rand_r</font>(seed)%5; - <font color=#008888>ACE_OS::sleep</font>(abs(delay)+1); - - <font color=red>// These should be randomly spaced like all of the other</font> - <font color=red>// post-sleep messages.</font> - ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t|%T)\<font color=#008888>tTest::svc</font>() Chaos and anarchy for all!\n</font>")); - - return(0); -} - -<font color=red>/* Our test application... - */</font> -int main(int, char**) -{ - <font color=red>// Create the test object with 10 threads</font> - Test test(10); - - <font color=red>// and open it to test the barrier.</font> - test.open(); - <font color=red>// Now wait for them all to exit.</font> - test.wait(); - - <font color=red>// Re-open the Test object with just 5 threads</font> - test.threads(5); - test.open(); - <font color=red>// and wait for them to complete also.</font> - test.wait(); - - return(0); -} -</PRE> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page03.html">Continue This Tutorial</A>]</CENTER> - |