PYTHONDONTWRITEBYTECODE documentation is incorrect

Documentation

PYTHONDONTWRITEBYTECODE is documented in Doc/using/cmdline.rst as:

If this is set to a non-empty string, Python won't try to write .pyc files on the import of source modules.

This is incorrect. The variable is obtained in Python/initconfig.c as:

    int dont_write_bytecode = 0;
    _Py_get_env_flag(use_env, &dont_write_bytecode, "PYTHONDONTWRITEBYTECODE");
    if (dont_write_bytecode) {
        config->write_bytecode = 0;
    }

and _Py_get_env_flag reads the environment variable value as integer, treating non-integer string as 1. Specifically, this means that PYTHONDONTWRITEBYTECODE=0 will not suppress writing .pyc files, even though the environment variable is assigned a non-empty string "0".

Linked PRs

• gh-143144

Comienza en Doc/using/cmdline.rst y compara el comportamiento documentado con Python/initconfig.c, especialmente la llamada a _Py_get_env_flag mostrada en el issue. Actualiza la descripción de la variable de entorno para que su análisis de enteros y el comportamiento de PYTHONDONTWRITEBYTECODE=0 sean precisos; la documentación estará terminada cuando la redacción coincida con la implementación.