Re: Interprocess communication using message queue

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Here is my Code Snippet.

In the first process:

MSGQUEUEOPTIONS msgopts, msgopts1;
HANDLE hq, hq1;
DWORD size, flag;
msgopts.dwSize = sizeof(MSGQUEUEOPTIONS);
msgopts.dwFlags = MSGQUEUE_ALLOW_BROKEN;
msgopts.dwMaxMessages = 10;
msgopts.cbMaxMessage = 10;
msgopts.bReadAccess = TRUE;
hq = CreateMsgQueue(TEXT("DLLTEST11"), &msgopts);
DWORD err = GetLastError();

msgopts1.dwSize = sizeof(MSGQUEUEOPTIONS);
msgopts1.dwFlags = MSGQUEUE_ALLOW_BROKEN;
msgopts1.dwMaxMessages = 10;
msgopts1.cbMaxMessage = 10;
msgopts1.bReadAccess = TRUE;
hq1 = CreateMsgQueue(TEXT("DLLTEST11"), &msgopts1);
DWORD err1 = GetLastError();

if(WriteMsgQueue(hq, &lpBuffer, sizeof(LPVOID), INFINITE, 0x00)==TRUE)
{
MessageBox(TEXT("SUCCESS"), TEXT("AAAAA"), NULL);
}
if(ReadMsgQueue(hq1, &lpBuffer1, sizeof(LPVOID), &size, 2000, &flag)== TRUE)
{
MessageBox((LPCTSTR) lpBuffer1, TEXT("YAHOO"), NULL);
}
else
{
DWORD err = GetLastError();
MessageBox(TEXT("FAIL"), TEXT("FAIL"), 0);
}

CloseMsgQueue(hq);
CloseMsgQueue(hq1);

And in my Second process I try to access this queue again to read the data,

MSGQUEUEOPTIONS msgopts1;
HANDLE hq1;
DWORD size, flag;

msgopts1.dwSize = sizeof(MSGQUEUEOPTIONS);
msgopts1.dwFlags = MSGQUEUE_ALLOW_BROKEN;
msgopts1.dwMaxMessages = 0;
msgopts1.cbMaxMessage = 10;
msgopts1.bReadAccess = TRUE;
hq1 = CreateMsgQueue(TEXT("DLLTEST2"), &msgopts1);
DWORD err1 = GetLastError();

if(ReadMsgQueue(hq1, &lpBuffer1, sizeof(LPVOID), &size, 2000, &flag)== TRUE)
{
MessageBox(NULL, (LPCTSTR) lpBuffer1, TEXT("YAHOO"), NULL);
}
else
{
DWORD err = GetLastError();
MessageBox(NULL, TEXT("FAIL"), TEXT("FAIL"), 0);
}

CloseMsgQueue(hq1);


Thanks
Khris


"Alex Feinman [MVP]" wrote:

> calling Create twice is correct. Could you post some code snippets to show
> how you read and write?
>
> --
> Alex Feinman
> ---
> Visit http://www.opennetcf.org
> "Khris" <Khris@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
> news:2286BE73-C6E5-4357-AFB0-102B49D7530D@xxxxxxxxxxxxxxxx
> > Hello,
> >
> > I am developing an application using EVC++ and I am using message queue
> > for interprocess communication. I am able to read the data that I write
> > into
> > the queue using ReadMsgQueue in the same process but when I try to read
> > data
> > that is there in the queue in another process it fails. Is there something
> > that I am missing. The error I get is 1460, Error_TIMEOUT.
> >
> > I have createMsgQueue twice in each process, to get the read handle and
> > the write handle respectively. Do I have to use any other API's like
> > OpenMsgQueue too.
> >
> > Thanks in advance
> > Khris
>
>
.

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