After window resizing, font size changes, etc., how can I easily and quickly check what is the current display width of my terminal?
How can I quickly check exactly how many columns my terminal has?
terminal;display
This has been answered (and mis-answered) repeatedly.  But:tput cols provides information that the operating system can tell you about the width.the COLUMNS variable may be set by your shell, but (a) it is unreliable (set in certain shells) and has the drawback that if exported will interfere with full-screen applications.the resize program can tell you the size for special cases where the terminal cannot negotiate its window-size with the operating system.Further reading: COLUMNS in the ncurses manual page.