First off, it's incredibly hard to read your question. Please fix that.

Secondly, as for your question itself, you seem to be asking "how can I clear out any characters waiting in the input buffer for a particular filehandle". The easiest way to accomplish this is with the Term::ReadKey module: 

use Term::ReadKey;
# ... do some stuff to the filehandle COMPORT ...
# ... do the command that gives the long response ...

# Clear the remaining input
while (defined(ReadKey(0.1,COMPORT))) {}
# ... do some other command ...

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That code will pull characters until the RX buffer is empty and will wait 0.1 seconds on an empty RX buffer to decide that it's really done. You can use "-1" if you want it to exit as soon as the RX buffer is empty and not wait.

I do hope that you're using sysread or some similar unbuffered system to deal with serial ports - otherwise, you'll have all sorts of trouble. 

--
@/=map{[/./g]}qw/.h_nJ Xapou cets krht ele_ r_ra/;
map{y/X_/\n /;print}map{pop@$_}@/for@/

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In reply to Re: How to flush the data accumulated in COM port buffer by fizbin
in thread How to flush the data accumulated in COM port buffer by Anonymous Monk

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