DragonFlyBSD

It would be nice, if the default values for row and col wouldn't be duplicated by this change.
The errno variable should be explicitly set to 0 before calling strtol, when you want to check errno != 0 afterwards.
Also we it would make sense to fallback to default values when negative values are given for COLUMNS or LINES.

Note that there are a few other places which call getenv("LINES") or getenv("COLUMNS") throughout nvi, which .
As an alternative instead of silently falling back to default values, it might make sense to abort vi with an error message, if we would crash anyway afterwards.

Note that there is an active upstream project for DragonFly's vi: <https://github.com/lichray/nvi2&gt;, which might be a better place to submit and discuss this change.

Fixed in b1ac2ebbae87355f573dc3a7ee05ea5756e778f7

Tested and it is no longer an issue.