I think that 255 already is *plenty*
(look at a 255 character long example string, you'll agree...).
While I'm writing this, I think we should maybe go for just 250,
to allow the leading "0 " in the line and maybe a leading "~" or "_" etc.,
to allow a trailing zero character (in C/C++ representation) and still be <= 255 for the whole line contents,
simply to avoid unnecessary trouble with existing tools (I know of no such trouble).
(look at a 255 character long example string, you'll agree...).
While I'm writing this, I think we should maybe go for just 250,
to allow the leading "0 " in the line and maybe a leading "~" or "_" etc.,
to allow a trailing zero character (in C/C++ representation) and still be <= 255 for the whole line contents,
simply to avoid unnecessary trouble with existing tools (I know of no such trouble).