🚀 go-pugleaf

Colin B Maharaj wrote:
> 
> Firstly, sorry the code is poorly designed, but works!
> I cut and paste from some code I have. Call EnumSerialPorts() and
> return it into an AnsiString. The return value is a csv list of the
> COM ports that exists. NOTE: This code does not say if it is in use.
> 
> If you call code to open a comport and it cannot be opened then
> either it is in use or it does not exists.
> 

Ahhh you mean COM Port.

You can test the existance of a COM port using the CreateFile() function.

Here's a simple function to test if a COM port exists. (It's a little crude)

bool ComPortExists(int ComPortNumber)
{
   HANDLE Handle;
   char Buffer[100];
   bool Ret = false;

   sprintf(Buffer, "\\\\.\\COM%d", ComPortNumber);
   Handle = CreateFile(Buffer, 0, 0, 0, OPEN_EXISTING,
     FILE_ATTRIBUTE_NORMAL, 0);
   // Notes: If Handle == INVALID_HANDLE_VALUE *AND*
   // if errno == 5 the port does exist, but cannot be opened ...
   // if errno == 2 doesn't exist, otherwise error.
   if ((Handle != INVALID_HANDLE_VALUE) || (GetLastError() == 5)) {
     CloseHandle(Handle); // Not sure if this is necessary. Probably not.
     Ret = true;
   }
   return Ret;
}