On Sun, 18 Apr 2010, Lars Nilsson wrote:

> As Unix shells (most if not all) use ! for special purposes, the option
> value would have to be quoted (using single quotes) to prevent an attempt to
> expand it to during command line parsing. Perhaps something like ~ could be
> used instead (at least I don't think it should be a problem despite being
> used to designate home directory for some programs)? Just food for thought.

Or perhaps just + and - ?

Like --proto +ftp,http would mean only enable those protocols while --proto
-ftp,http would mean enable all protocols except the named ones.

The downside is perhaps that starting with a dash/minus makes it look like an
option...

-- 
  / daniel.haxx.se
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