[Groff] What is the best way to document how to enable SGR codes for groff's terminal output?

[Gavin Smith]

(Please CC me in any responses.)

Hello,

>From what I can tell, SGR codes are on by default for terminal output
for groff. They can be turned off by setting the GROFF_NO_SGR
environmental variable. However, it seems that many distributions of
groff have added another variable, GROFF_SGR, which is needed to turn
these codes *on*.

This is an issue with the standalone Info browser that is part of
texinfo, which can pass through SGR codes when displaying man pages,
but cannot display in bold and underline if the older "overstrike"
method is used.

I'm posting to see if anyone knows what the best way to document this
is. Could groff document it as a variable that doesn't do anything, or
could distributions of groff document it somehow? I don't know if it
is a good idea to document GROFF_SGR in programs which use groff's
output when it is not an "official" variable.

Thanks,

Gavin