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diff --git a/docs/tutorials/021/page03.html b/docs/tutorials/021/page03.html deleted file mode 100644 index e2d6e0bf117..00000000000 --- a/docs/tutorials/021/page03.html +++ /dev/null @@ -1,146 +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 021</TITLE> -</HEAD> -<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F"> - -<CENTER><B><FONT SIZE=+2>ACE Tutorial 021</FONT></B></CENTER> - -<CENTER><B><FONT SIZE=+2>Pooling your memories</FONT></B></CENTER> - -<P> -<HR WIDTH="100%"> - The client side is a little simpler than the server. Mainly - because we don't try to delete the pool: - <ul> - <li>Create an Allocator to access the pool - <li>Find the named region - </ul> -<hr> -<PRE> - -<font color=red>// $Id$</font> - -<font color=blue>#include</font> "<font color=green>mpool.h</font>" - -<font color=blue>#if defined</font>(<font color=purple>ACE_LACKS_SYSV_SHMEM</font>) -int -main (int, char *[]) -{ - ACE_ERROR_RETURN ((LM_ERROR, - "<font color=green>System V Semaphores not available on this platform.\n</font>"),100); -} -#else <font color=red>// ACE_LACKS_SYSV_SHMEM</font> -int -main (int, char *[]) -{ - <font color=red>/* - Use the same pool name used by the server when we create our - Allocator. This assures us that we don't create a whole new - pool. - */</font> - Allocator allocator (<font color=#008888>Constants::PoolName</font>); - - <font color=red>/* - You can put anything in the memory pool. Not just the - character array we want. The find() method till, therefore, - return a void* that we will have to cast. - */</font> - void *region; - - <font color=red>/* - We use find() to locate a named region in the pool. This is - the counterpart to bind() used in the server. - Here, we go try to find the region that the server has created - and filled with data. If there was a problem getting the pool - or finding the region, we'll get back -1 from find(). - */</font> - if (allocator.pool ().find (<font color=#008888>Constants::RegionName</font>,region) == -1) - ACE_ERROR_RETURN ((LM_ERROR, - "<font color=green>Cannot find the name '%s'\n</font>", - <font color=#008888>Constants::RegionName</font>), - 100); - - <font color=red>/* - Since find() returns us a void*, we cast it here to the char* - that we want. - */</font> - char *shm = (char *) region; - - ACE_DEBUG ((LM_INFO, - "<font color=green>Shared memory is at 0x%x\n</font>", - shm)); - - <font color=red>/* - The same pair of semaphores as used by the server are created - here. We probably don't need the CREATE flag since the server - should have already done that. There may be some very small - windows, however, where the server would have created the - memory pool but not yet gotten to the semaphores. - */</font> - ACE_SV_Semaphore_Complex mutex; - ACE_ASSERT (mutex.open (<font color=#008888>Constants::SEM_KEY_1</font>, - <font color=#008888>ACE_SV_Semaphore_Complex::ACE_CREATE</font>, - 0) != -1); - - ACE_SV_Semaphore_Complex synch; - ACE_ASSERT (synch.open (<font color=#008888>Constants::SEM_KEY_2</font>, - <font color=#008888>ACE_SV_Semaphore_Complex::ACE_CREATE</font>, - 0) != -1); - - <font color=red>/* - It doesn't matter if we created 'mutex' or if the server did. - In either case, it was created in a locked state and we will - block here until somebody unlocks it. In our scenario, that - will have to be the server. - */</font> - if (mutex.acquire () == -1) - ACE_ERROR_RETURN ((LM_ERROR, - "<font color=green>(%P) client mutex.acquire</font>"), - 1); - - <font color=red>/* - Now that we know it is safe to access the data, we'll run - through and make sure that it contains what we think the server - supplied. - */</font> - for (int i = 0; i < <font color=#008888>Constants::SHMSZ</font>; i++) - ACE_ASSERT (<font color=#008888>Constants::SHMDATA</font>[i] == shm[i]); - - <font color=red>/* - Look back at the server. After filling the region, it will - attempt to acquire the lock on 'synch'. It will wait there - until we release() the semaphore. That will allow it to remove - the pool and cleanup. We can simply exit once we perform the - release. (Ok, a free() of the region would probably be polite...) - */</font> - if (synch.release () == -1) - ACE_ERROR_RETURN ((LM_ERROR, - "<font color=green>(%P) client synch.release</font>"), - 1); - - return 0; -} - -<font color=red>/* - Again, we have the necessary explicit template instantiations - because I based this on an ACE example instead of creating it from scratch. - */</font> -<font color=blue>#if defined</font> (<font color=purple>ACE_HAS_EXPLICIT_TEMPLATE_INSTANTIATION</font>) -template class ACE_Malloc<ACE_MMAP_MEMORY_POOL, ACE_SV_Semaphore_Simple>; -template class ACE_Guard<ACE_SV_Semaphore_Simple>; -template class ACE_Write_Guard<ACE_SV_Semaphore_Simple>; -template class ACE_Read_Guard<ACE_SV_Semaphore_Simple>; -<font color=blue>#elif defined</font> (<font color=purple>ACE_HAS_TEMPLATE_INSTANTIATION_PRAGMA</font>) -<font color=blue>#pragma</font> <font color=purple>instantiate</font> ACE_Malloc<ACE_MMAP_MEMORY_POOL, ACE_SV_Semaphore_Simple> -<font color=blue>#pragma</font> <font color=purple>instantiate</font> ACE_Guard<ACE_SV_Semaphore_Simple> -<font color=blue>#pragma</font> <font color=purple>instantiate</font> ACE_Write_Guard<ACE_SV_Semaphore_Simple> -<font color=blue>#pragma</font> <font color=purple>instantiate</font> ACE_Read_Guard<ACE_SV_Semaphore_Simple> -<font color=blue>#endif</font> <font color=red>/* ACE_HAS_EXPLICIT_TEMPLATE_INSTANTIATION */</font> - -<font color=blue>#endif</font> <font color=red>/* ACE_LACKS_SYSV_SHMEM */</font> -</PRE> -<P><HR WIDTH="100%"> -<CENTER>[<A HREF="../online-tutorials.html">Tutorial Index</A>] [<A HREF="page04.html">Continue This Tutorial</A>]</CENTER> |