How to add comments to an Exuberant Ctags config file?

Question

What character can I use to put comments in an Exuberant Ctags .ctags file?

I would like to add comments with explanations, and perhaps to disable some rege

Answer 1

You can't! I looked through the source code (thanks to apt-get source). There are no checks for lines to ignore. The relevant code is in parseFileOptions() in options.c

But sometimes comments are a neccessity, so as a workaround I put a comment in as a regexp, in such as way that it is unlikely to ever match anything.

--regex-coffee=/^(COMMENT: Disable next line when using prop tag)/\1/X,XXX/

The ^ helps the match to fail quickly, whilst the ( ) wrapper is purely for visual effect.

Your comment should be a valid regexp, to avoid warnings on stderr. (That means unescaped /s must be avoided, and if you use any [ ] ( or )s they should be paired up.) See Tom's solution to avoid these restrictions.