Thread: WaitCommEvent()????

Hi:
Here is to monitor the any character arrives in COM Port

Code:

while(TRUE)
{
    if (!WaitCommEvent(COM1, &dwCommEvent, &osStatus))
   {
        if (GetLastError() != ERROR_IO_PENDING)	  // Wait not delayed!!
       {
         							/*ERROR HANDLING HERE*/ 			

       }
       else
     //   while(TRUE)
        //{
                deRes = WaitForSingleObject(osStatus.hEvent,3000);
                switch(deRes)
               {
                    case WAIT_OBJECT 0:
                    /*osStatus.hEvent gets signaled*/
                    break;
                     case WAIT_TIMEOUT:
                    MessageBox(0,"timeouts","ok",MB_OK);
                    break;
                    default:
                    ............
                    break;
               }
       //    }//end while(TRUE)
       }
}

Here I hope those varaibles are cleared with the names.

The problem is that the GetLastError() is not pending after the first round WM_TIMEOUT,I just can't say the reason, but is there any way to avoid the error if I want to restart from WaitCommEvent() after every WM_TIMEOUT??
Thanx for the help!!!

Not gone thru your code fully. Just skimmed it but found an error.
Think you missed a brace { changing the meaning of the code.

Try

Code:

//I like to have a loop variable
int iLoop=TRUE;
while(iLoop)
{
    if (!WaitCommEvent(COM1, &dwCommEvent, &osStatus))
   {
        if (GetLastError() != ERROR_IO_PENDING)	  // Wait not delayed!!
       {
         	/*ERROR HANDLING HERE*/ 			

       }
       else
       {//this brace is missing 
                deRes = WaitForSingleObject(osStatus.hEvent,3000);
                switch(deRes)
               {
                    case WAIT_OBJECT 0:
                    /*osStatus.hEvent gets signaled*/
                    break;
                     case WAIT_TIMEOUT:
                    MessageBox(0,"timeouts","ok",MB_OK);
                    break;
                    default:
                    ............
                    break;
               }
       }
   }
   else //is this where we should exit?
	iLoop=FALSE;
}

Thanks, but what I should do if I don't want to quit while() loop? some problem occurs in WaitCommEvent() after the first timeouts.

Thanks alot

I'm not sure what you want to do so....

Code:

do//until we get the object signaled
{
           deRes = WaitForSingleObject(osStatus.hEvent,3000);
           if(deRes ==WAIT_OBJECT )
           {                    
                    /*osStatus.hEvent gets signaled*/
                    //set main loop var here to exit?
           }
           else if(//error occurs)
           //ect
}
while (deRes==WAIT_TIMEOUT)//three seconds passed without change