)Le lun. 13 mai 2019 à 18:28, Steve Dower steve.dower@python.org a écrit :
My take:
- all the examples are trying to be isolated from the system Python
install (except Vim?)
"Isolation" means different things:
* ignore configuration files * ignore environment variables * custom path configuration (sys.path, sys.executable, etc.)
It seems like the most common need is to have a custom path configuration.
Py_IsolatedFlag isn't used. Only py2app manually ignores a few environment variables.
- all the examples want to import some of their own modules before
running user code
Well, running code between Py_Initialize() and running the final Python code is not new, and my PEP doesn't change anything here: it's still possible, as it was previously. You can use PyRun_SimpleFile() after Py_Initialize() for example.
Maybe I misunderstood your point.
- nobody understands how to configure embedded Python :)
Well, that's the problem I'm trying to solve by designing an homogeneous API, rather than scattered global configuration variables, environment variables, function calls, etc.
Also from my own work with/on other projects:
- embedders need to integrate native thread management with Python threads
Sorry, I see the relationship with the initialization.
- embedders want to use their own files/libraries
That's the path configuration, no?
- embedders want to totally override getpath, not augment/configure it
On Python 3.7, Py_SetPath() is the closest thing to configure path configuration. But I don't see how to override sys.executable (Py_GetProgramFullPath), sys.prefix, sys.exec_prefix, nor (internal) dll_path.
In the examples that I found, SetProgramName(), SetPythonHome() and Py_SetPath() are called.
My PEP 587 allows to completely ignore getpath.c/getpath.c easily by setting explicitly:
* use_module_search_path, module_search_paths * executable * prefix * exec_prefix * dll_path (Windows only)
If you set these fields, you fully control where Python looks for modules. Extract of the C code:
/* Do we need to calculate the path? */ if (!config->use_module_search_paths || (config->executable == NULL) || (config->prefix == NULL) #ifdef MS_WINDOWS || (config->dll_path == NULL) #endif || (config->exec_prefix == NULL)) { _PyInitError err = _PyCoreConfig_CalculatePathConfig(config); if (_Py_INIT_FAILED(err)) { return err; } }
OpenOffice doesn't bother with complex code, it just appends a path to PYTHONPATH:
setenv("PYTHONPATH", getenv("PYTHONPATH") + ":" + path_bootstrap);
It can use PyWideStringList_Append(&config.module_search_paths, path_bootstrap), as shown in one example of my PEP.
Victor -- Night gathers, and now my watch begins. It shall not end until my death.