Hi,
I have a custom csv export file that's very helpful to me. I'd like to modify it by adding 2 columns to the headers but not have MP3Tag put any data in those fields. Is there something like %_blank% that I can use? If not are there existing placeholders that usually don't return data?
TIA
laffin_boy
%dummy%
But don't take it personally. 
I doubt that %dummy% works for writing.
If you export to csv then the delimiter between fields is the semicolon.
So, something like
%artist%;;;%title%;
Should produce 2 empty columns between the artist data and the title.
I just tested a csv export and %dummy% works fine.
I bet it works because it is just the very long version of ;;;
Anyway: we found a solution. that should suffice.
In Mp3tag the percent characters around a name work as a "content operator", that means it is the reference to the value of a variable with such name, this manifestation is not a placeholder.
The problem with the value %dummy% is, when a script variable or a tag-field with the name DUMMY really does exist in the script environment or in the tag area, then %dummy% delivers a real value, which might vary from nothing.
DD.20140204.0815.CET