Pythonista 3.5: Does not reset `stdin/stdout/stderr` on new script execution

[o-murphy]

If some script change sys.stdout, sys.stderr, sys.stdin on runtime, there are no reset to original ones on second and future scripts executions. All next executions will use redefined IO, in some cases it won't print nothing. The only way to fix it is reload sys module or restart the app.

Is there way to setup force sys/interpreter/environment reset on next script execution? For now I can avoid it just with adding shortcut to the script with reset environment flag

This behaviour can be represented with this small snippets
Run script1.py and then script2.py

# script1.py
import sys

class FakeStream:
    def write(self, s, no_wait=False):
        pass # assume this stream have no output

print("sample text 1")  # output: sample text 1
sys.stdout = FakeStream()
print("sample text 2")  # No output there

# script2.py
print("sample text 3")  # No more output there till `sys` reload or Pythonista restart

P.S.: For example it happen every time the StaSh launched. It overwrites sys and then neither ansi escape codes will work in the console

[omz]

Good point!

I guess, being able to overwrite stdout across script launches could be seen as a feature (for customizing Pythonista's output), but in most cases, it would probably make sense to always reset stdout/stderr to the default streams.

[o-murphy]

Good point!

I guess, being able to overwrite stdout across script launches could be seen as a feature (for customizing Pythonista's output), but in most cases, it would probably make sense to always reset stdout/stderr to the default streams.

I would suggest making this feature optional in the settings. But this possibility must be present.

[o-murphy]

Py3.14 adds

iOS and macOS apps can now be configured to redirect stdout and stderr content to the system log. (Contributed by Russell Keith-Magee in gh-127592.)

Backported to py3.13?

• gh-126925: Modify how iOS test results are gathered python/cpython#127592 (comment)

This is interesting, but not relevant to this issue discussion subject.