idlwave-header-to-beginning-of-file

idlwave-header-to-beginning-of-file is a variable defined in `idlwave.el'.
Its value is

t

Documentation:
Non-nil means, the documentation header will always be at start of file.
When nil, the header is positioned between the PRO/FUNCTION line of
the current routine and the code, allowing several routine headers in
a file.

You can customize this variable.