I'm working on a perl script that plots the output of 'ping'. It's working very nicely, thanks, except that I don't know the terminal width/# of columns, especially if the window gets resized whilst running. I have tried: 
 
my $w = $ENV{COLUMNS};

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...which returns an empty string. This kludge-code works (please forgive noisy use of many variables, under development), but not dynamically, and only following 

export COLUMNS

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before launch: 

# get current width from environment
    chomp (my $w = `echo \$COLUMNS`);
    if ($w) {
      $width = $w - 5;
    }

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Can someone point me to a simple, working solution? Thanks!

In reply to Need nudge: how to (dynamically) discover terminal width? by polypagan

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