> IMHO either of these solutions would be fine.
> 
> * have a PyOS_PutEnv() function, gettext has gettext_putenv() to
> workaround this problem.

This solution would help in many other cases as well, so adding
such an API would certainly help more than specialized interfaces.

> * manage this the same as Py_GetPythonHome(), which can be defined by
> the embedding application to override the default.

I think you meant Py_SetPythonHome().

Given that the IO encoding is very important for Python 3.x, a special
API just for setting the encoding may be useful to have as well.

Care must be taken, though, that the encoding cannot be set after
Py_Initialize() has been called.

It may overall be easier to go with the PyOS_PutEnv() solution to
not run into the problems with having to check for an initialized
interpreter first.

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