I need to (re-)generate some tables as *.qbk files before building the documentation proper.

# Generate Quickbook tables of types and their numeric_limits.
run fixed_point_types_table.cpp ;

writes the files

How do I ensure that

1  The files are only re-generated when the source .cpp has changed ( been edited).

2  The files are written before the main Quickbook is processed to xml with

xml fixed_point
  :
    fixed_point.qbk
  :
    <dependency>autodoc # doxygen
  ;

I looks as though I need a <dependency>

but I can't see what the target would be called.

3  I may have more than one .cpp file to run.  How can I run all the .cpp in the (doc/) folder?