[Python-ideas] Combining stat/lstat/fstatat etc.

[Serhiy Storchaka]

In Python3 added a large number of "at"-functions from the latter Posix standard. Such a large number of names only litters namespace. In C it is necessary for historical reasons (note that fstatat combines the stat and lstat and includes the possibility of extension) and because of static typing. But in Python because of dynamic typing we can extend existing functions.

So instead of stat, lstat, and fstatat could use the same function `stat(path, *, dirfd=None, followlinks=True)`. Then `lstat(path)` == `stat(path, followlinks=False)`, and `fstatat(dirfd, path, flags)` == `stat(path, dirfd=(AT_FDCWD if dirfd is None else AT_FDCWD), followlinks=not (flags & AT_SYMLINK_NOFOLLOW))`. As special value for dirfd I suggest using the None, not AT_FDCWD (it's more pythonish). fstat could be included too, by specifically treating the case where the path is integer.

And same for other functions.

Old lstat and lchown will remain for compatibility as light wrappers around the stat, with time they may become deprecated.