distutils install dir

[John Hunter]

What is the best way to get the target install dir from distutils when 

  python setup.py install 

is run.

Eg, on a standard python install to /usr/local I want

/usr/local/lib/python2.3/site-packages

and on a standard win32 python installation I want
c:\\Python23\\Lib\\site-packages

I also want to handle the case when an alternate prefix is installed.

To to ask the question another way.  I want to add SomeFile.pth to the
install dir.  For various reasons, extra_path is not a good choice for
me.  I just want to copy a file SomeFile.pth to the site-packages dir.
My workaround is to treat SomeFile.pth as a data_file, and add it to
the site-packages dir (stored in sitep) with

    data_files = [ (sitep, 'SomeFile.pth') ]


setup(name="somemod",
      ..snip...
      ext_modules = ext_modules, 
      data_files=data_files,
      )

Thanks,
John Hunter