In my experience, getting serial ports working with the higher-level reading functions (also timeouts and graceful closing of the ports) can be quite finicky. In fact, in a recent script I wrote that does something similar to yours, I just read the port one byte at a time and do the buffering myself, it's not the most elegant but it's robust. The code resembles the "EXAMPLE" in Device::SerialPort.

However, from perlvar:

HANDLE->autoflush( EXPR ) ... This has no effect on input buffering. See getc for that.

I don't see you writing to the port anywhere. So I don't think "autoflush" is the right term here, and perhaps you need to explain your problem better: In regards to what is being read/written from the port, what exactly is the expected behaviour, and what behaviour are you getting instead? Perhaps a short sample would help?

How can I create a filehandle for this module that it will always return me the last line from the serial port output?

By "last", do you mean "most recent"? I see a couple of options: Keep the port closed until you actually want to read; continually read the port and just remember the most recent line; or try the lookclear method from Device::SerialPort (although the docs are a little unclear to me whether lookclear will do what you need).

In reply to Re: serial port tied filehandle autoflush by Anonymous Monk
in thread serial port tied filehandle autoflush by kkaiser

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