Re: typo in accept-process-output (process.c)

[Richard Stallman]

    So the job only has to be done once, what replacement will people be
    happy with? Personally, I think plain "if" would be just fine, except
    perhaps to the tediously literal-minded.

In some cases, just "if" is clear.

                                             Failing that, "only if".
    As a last resort, "if and only if" (yuck).

Where just "if" is not clear, you need to get creative.  Find a
rewrite which is clear.  "If and only if" is ok when you need it, but since it 
is a bit longer, you might look for a better method.