Well, MikTex contains texi2dvi.exe, so I renamed this to texi2pdf.exe
and added its directory to the MinGW path. lilypond-book and
Reinhold's code then seems to work correctly, provided I comment
out the _sleep call in threading.py and use the following command in line
208 of book_texinfo.py:
cmd = '%s -c -p %s' % (global_options.texinfo_program, tmpfile);
As the sleep call in threading.py is a hack to satisfy Solaris this should
anyway be bypassed for other platforms, so I've changed my mind -
this seems a reasonable change to make.
I'm now going to reinstall 2.15.25, make exactly these changes, and
try again to double-check this is adequate. The changes would then
need to be bracketed with a test for the platform.