[GRASS-dev] Handling of Python scripts on MS Windows

[Markus Metz]

On Wed, Apr 23, 2014 at 1:37 AM, Glynn Clements
<glynn at gclements.plus.com> wrote:
>
> Markus Metz wrote:
>
>> Therefore it is IMHO not a good idea to rely on a system-wide Python
>> file association on MS Windows,
>
> Regardless of whether or not it's a good idea, it's not entirely
> avoidable.

Sure it is.
>
> If a process "executes" a command using the system's interfaces
> (system(), CreateProcess(), subprocess.Popen(), batch files, etc), and
> that command refers to a Python script, the registry's .py file
> association *will* be used.

You ignore my suggestion to use .bat files calling the embedded script
interpreter, like in GRASS 6.

>
>> and therefore I propose to use the
>> embedded Python version already coming for some years with the
>> WinGRASS installer.
>
> You can only force the use of a specific Python interpreter when
> you control the execution mechanism. Otherwise, the system's file
> associations will be used.

You ignore my suggestion to use .bat files calling the embedded script
interpreter, like in GRASS 6.

>
> Users who aren't willing to live within whatever walled garden you
> provide will have to have a valid system-wide Python installation. In
> that situation, that installation should be used always, not just for
> those cases where you can't interpose your workaround.

You missed the point. I do not want to use a walled garden. Just set
the GRASS environment as currently done and off you go (with .bat
files, not with .py files).

>>
>> I suspect the whole discussion boils down to the question whether we
>> can rely on GRASS-compatible Python file associations on MS Windows or
>> not. I say, we can not.

[Your answer here]

>
> For me, the discussion boils down to:
>
> 1. How invasive is this workaround going to be with regard to the rest
> of GRASS?

For using system-wide .py file associations, nobody tried, so nobody
knows, thus maximal.
>
> 2. How easy is it to disable this workaround and just use the system
> Python instead?.

IMHO an invalid question because an existing Python file association
on MS Windows can change or disappear any time, and a GRASS
installation will not be notified about this change.

>
> Batch files are a better solution, as they don't affect anything else,
> and it's a simple matter to either delete them or modify PATH to
> ignore them, and use the Python scripts directly.

Sounds good.

Markus M