HyperTerminal is a Windows program, but your code seems to be for a *NIX system? Is this two different computers? Are you sure your serial device works on the *NIX system?

If you're sure about the baud rate and the other settings (including flow control, handshake, etc.), then it's hard to guess what is going on without knowing the details of your software & hardware set-up - at least I'm at a loss at the moment, perhaps someone else has seen a similar problem. It might also help if you describe what kind of a device you're talking to, whether it is a "real" hardware serial port or a USB adapter, etc.

some ACK response

Could you perhaps be more specific, like show a short example session?

To pick up on some of the things you wrote earlier:

How can i really tell whether my command did go through OK.

The only way to really tell what's physically going on is to look at the signal on the wires with a logic analyzer or oscilloscope. On the PC side, in my experience it's usually a matter of making sure that there's only one software trying to access the port at once, and getting all of the settings right.

I know my response to the serial port is not what I am seeing here.

How did you determine this?

In reply to Re^2: Using Device::SerialPort by Anonymous Monk
in thread Using Device::SerialPort by hardy004

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