Im not sure if this will help, but I believe one can also alter the internal buffer options using in-built attributes of the Win32::seialport module.
However, it would be much better if you could post your code to be more specific.

If you want to see data as and when they come and see it NOW, then have a look at Perl Idioms Explained - $|++
SRK.

In reply to Re: win32::serialport buffer overflow by rupesh
in thread win32::serialport buffer overflow by Anonymous Monk

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