I'm trying to use the doxygen tool with b2, and I have a few questions:
Looking at the JAM code it seems the logic is laid out for the tool to generate a "doxyfile" from any parameters given to the `doxygen` rule, then invoke the "doxygen" executable with that.
How can I invoke doxygen (that is, the `doxygen` rule, not the
executable) to use an existing doxyfile, instead of generating it
-- ...ich hab' noch einen Koffer in Berlin...