recalculate LINES and COLUMNS

[thomas]

Hi list,

Sometimes I want to change the font of my terminal (urxvt): for
instance, I am tired and want a bigger font. I can use a bash alias
(or a keyboard shortcut) which runs these two lines:

printf '\e]710;%s\007' 'xft:DejaVu Sans Mono:size=10'
kill -WINCH $$

Font is changed but the second line seems to have no effect: bash does
not recompute the values of COLUMNS and LINES, thus I may type
"outside urxvt's window".

There is a "checkwinsize" option but it does not seem to help.

If I manually resize the window, the problem is fixed.

How can I send a WINCH signal to bash so that it recalculates the
correct values of LINES and COLUMNS after a font change?

Thanks
Thomas