minimal changes to os.py

python checks os-based assumptions at startup, some of  which can be
bypassed since this is Cosmopolitan Python.

third_party/python/Lib/os.py

@@ -38,24 +38,15 @@ def _exists(name):
     return name in globals()
 
 def _get_exports_list(module):
-    try:
-        return list(module.__all__)
-    except AttributeError:
-        return [n for n in dir(module) if n[0] != '_']
+    return getattr(module, "__all__", (n for n in dir(module) if n[0] != '_'))
 
 name = 'posix'
 linesep = '\n'
 from posix import *
-try:
-    from posix import _exit
-    __all__.append('_exit')
-except ImportError:
-    pass
+from posix import _exit
+__all__.append('_exit')
 import posixpath as path
-try:
-    from posix import _have_functions
-except ImportError:
-    pass
+from posix import _have_functions
 import posix
 __all__.extend(_get_exports_list(posix))
 del posix
@@ -67,7 +58,7 @@ from os.path import (curdir, pardir, sep, pathsep, defpath, extsep, altsep,
 del _names
 
 
-if _exists("_have_functions"):
+if True or _exists("_have_functions"):
     _globals = globals()
     def _add(str, fn):
         if (fn in _globals) and (str in _have_functions):

third_party/python/Modules/posixmodule.c

@@ -78,6 +78,8 @@
 
 PYTHON_PROVIDE("posix");
 PYTHON_PROVIDE("posix._getfinalpathname");
+PYTHON_PROVIDE("posix._exit");
+PYTHON_PROVIDE("posix._have_functions");
 
 /* POSIX module implementation */