Z:gnu-man-db-manpages--8c6240-If $B=3CMANWIDTH=3E is set, its va/en

If $B is set, its value is used as the terminal width (see the B<--long> option). If it is not set, the terminal width will be calculated using the value of $B, an B (2) if available, or falling back to 80 characters if all else fails.