RE: more CommEvents than expected

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Hello
After checking your code, it seems that following lines are called several
times even if WaitCommEvent is not called in the for loop. Since dwEvtMask
works like a global variable to the for(::) loops, that is why you always
get the EV code repeated.
//-----------------------------------------
if (proc)
{

if (dwEvtMask & EV_DSR) printf("ev_dsr pin six fPending = %d ",
fPending);
if (dwEvtMask & EV_CTS) printf("ev_cts pin eight fPending = %d ",
fPending);
if (dwEvtMask & EV_RING) printf("ev_ring pin nine fPending = %d ",
fPending);
if (dwEvtMask & EV_RLSD) printf("ev_rlsd pin one fPending = %d ",
fPending);
if (GetCommModemStatus(hCom, &dwCommStatus))
printf("commStatus = %x\n", dwCommStatus);
else
printf("Error = %d\n", GetLastError());
}
//----------------------------------------
You may use following ways to resolve this issue:
1> clear dwEvtMask every time when you get into the new loop, I suggest you
add dwEvtMask=0 as following:
for(;;)
{
dwEvtMask =0;
proc = 0;
if (!fPending)
/.....
2> or you can add the " if(proc) ..." above when WaitCommEvent return TRUE,
like following:
if (WaitCommEvent(hCom, &dwEvtMask, &o))
{
proc = 1;
// add them
here
}

Please let me know if my answer helps you resolve the problem. If there is
anything more I can assist you, please feel free to let me know.

Thanks,
Rhett Gong [MSFT]
Microsoft Online Partner Support
Get Secure! - www.microsoft.com/security

This posting is provided "AS IS" with no warranties and confers no rights.

.

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