Re: To find out console line size in char.s .

[johngg]

Expanding on robby_dobby's answer, if the terminal is resized it should generate a $SIG{ WINCH } so install a handler to recalculate terminal size on receipt of that signal.

$SIG{ WINCH } = sub { # get new terminal size here };

I hope this is helpful.

[robby_dobby]

Yes, but note that this may not be very portable:

use Config;

my @names = split ' ', $Config{sig_name};
print grep /WINCH/, @names;

This does not print anything on Windows, but gives me results on cygwin and Linux(Slackware). To OP: As always, read the documentation (man 7 signal). This SO post may also shed some light on SIGWINCH for Windows OSes.