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<HTML>
<HEAD>
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
<META NAME="Author" CONTENT="James CE Johnson">
<TITLE>ACE Tutorial 020</TITLE>
</HEAD>
<BODY TEXT="#000000" BGCOLOR="#FFFFFF" LINK="#000FFF" VLINK="#FF0F0F">
<CENTER><B><FONT SIZE=+2>ACE Tutorial 020</FONT></B></CENTER>
<CENTER><B><FONT SIZE=+2>Sharing your Memories with persistence</FONT></B></CENTER>
<P>
<HR WIDTH="100%">
I wanted to show placement new again & prove that you can use it with
a memory mapped file just as easily as with a shared memory
segment.
<p>
Imagine if you had an object that contained an image & then you mapped
that to a file... Instead of a bunch of jpg files laying
around, you would actually have objects instead. Save the
image? No problem, it's already there!
<hr>
<HR width=50%><P><center>server2.cpp</center><HR width=50%>
<PRE>
<font color=red>// $Id$</font>
<font color=blue>#include</font> "<font color=green>mmap.h</font>"
int
main (int, char *[])
{
ACE_Shared_Memory_MM shm_server (SHM_KEY, sizeof(SharedData) );
char *shm = (char *) shm_server.malloc ();
ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t) Memory Mapped file is at 0x%x\n</font>",
shm ));
SharedData * sd = new(shm) SharedData;
sd->set();
sd->available(0);
while ( ! sd->available() )
<font color=#008888>ACE_OS::sleep</font> (1);
sd->show();
if (shm_server.remove () < 0)
ACE_ERROR ((LM_ERROR, "<font color=green>%p\n</font>", "<font color=green>remove</font>"));
return 0;
}
</PRE>
<HR width=50%><P><center>client2.cpp</center><HR width=50%>
<PRE>
<font color=red>// $Id$</font>
<font color=blue>#include</font> "<font color=green>mmap.h</font>"
int main (int, char *[])
{
ACE_Shared_Memory_MM shm_client (SHM_KEY, sizeof(SharedData));
char *shm = (char *) shm_client.malloc ();
ACE_DEBUG ((LM_INFO, "<font color=green>(%P|%t) Memory Mapped file is at 0x%x\n</font>",
shm ));
SharedData * sd = new(shm) SharedData(0);
sd->show();
sd->set();
sd->available(1);
shm_client.close();
return 0;
}
</PRE>
<P><HR WIDTH="100%">
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