This should match the situation in the 1.6b1 tree.

they include prototypes.

char**) and return an int even on PC platforms. If not, please fix
PC/utils/makesrc.c ;-P

Python on UNIX now trusts PYTHONHOME unconditionally

Modules/getpath.c:

Landmark changed to os.py.

Setting PYTHONHOME now unconditionally sets sys.prefix
(and sys.exec_prefix). No further checks are done whether the
standard lib can be found in that location or not. This is in
sync with the PC subdir getpath implementations.

PC/getpathp.c:

Landmark changed to os.py.

PC/os2vacpp/getpathp.c:

Landmark changed to os.py.

Note: BAW's checkin on exceptions.c eliminates earlier concerns about
a bogus PYTHONHOME value leading to a core dump.  Instead it causes a
useless sys.path and prevents imports.

again (Mark Hammond is the cause of all this).

is now obsolete), and changed the default path calculations.
$PYTHONPATH is now added as a prefix (like it's always been on Unix);
$PYTHONHOME takes precedence over the program pathname; and only one
landmark is needed.

lives to the end of the path.

(Still to do: add $PYTHONPATH to the front instead of using it as is;
add the Win32 registry paths as in getpath_nt.c (which can then
retire).)