R help - Jan 2021 - Error when calling (R 4.0.x on Windows) from Python

>>>>> Marcel Baumgartner 
>>>>>     on Tue, 26 Jan 2021 08:55:48 +0100 writes:
    > Dear all, my colleague posted our issue on stackoverflow:

    > Calling R script from Python does not save log file in
    > version 4 - Stack Overflow
    >
[https://stackoverflow.com/questions/65887485/calling-r-script-from-python-does-not-save-log-file-in-version-4]

    > It is about this kind of call to R:

    > R.exe -f code.R --args "~/file.txt" 1>
"~/log.txt" 2>&1".

    > The issue is that the log.txt file is not created when
    > running R 4.x.x. The same code works perfectly fine with R
    > 3.6.x.

    > Any idea what's going wrong as of version 4? Regards
    > Marcel?

Dear Marcel,
I think the solution is embarrassingly simple:
>From the SO post, where she showed a bit more detail than you
show here, it's clear  you have confused
'R.exe' and 'Rscript.exe' and what you say above is not true:

'R.exe' was used for R 3.6.0  but for R 4.0.3, you/she used
'Rscript.exe' instead.

... as you've noticed now, they do behave differently, indeed!

Avec meilleures salutations,
Martin

>>>>> Martin Maechler 
>>>>>     on Tue, 26 Jan 2021 12:37:58 +0100 writes:
>>>>> Marcel Baumgartner 
>>>>>     on Tue, 26 Jan 2021 08:55:48 +0100 writes:
    >> Dear all, my colleague posted our issue on stackoverflow:

    >> Calling R script from Python does not save log file in
    >> version 4 - Stack Overflow
    >>
[https://stackoverflow.com/questions/65887485/calling-r-script-from-python-does-not-save-log-file-in-version-4]

    >> It is about this kind of call to R:

    >> R.exe -f code.R --args "~/file.txt" 1>
"~/log.txt" 2>&1".

    >> The issue is that the log.txt file is not created when
    >> running R 4.x.x. The same code works perfectly fine with
    >> R 3.6.x.

    >> Any idea what's going wrong as of version 4? Regards
    >> Marcel?

    > Dear Marcel, I think the solution is embarrassingly
    > simple:

    >> From the SO post, where she showed a bit more detail than you
    > show here, it's clear you have confused 'R.exe' and
    > 'Rscript.exe' and what you say above is not true:

    > 'R.exe' was used for R 3.6.0 but for R 4.0.3, you/she used
    > 'Rscript.exe' instead.


    > ... as you've noticed now, they do behave differently,
    > indeed!

Well, this was not the solution to their -- Windows-only -- problem.
The problem *is* indeed visible if they only use  R.exe  (also
for R 4.0.3).

I've commented more on the SO issue (see above),
notably asking for a *minimal* repr.ex. (reproducible example),
and one *not* using "<YOUR PATH>" and setwd() ..

Martin