Module platform 

Cross-platform filesystem differences, absorbed in one place.

Path separators, reserved names, and stream syntax differ enough between Windows and Unix that scattering the checks would guarantee one of them is forgotten. ROADMAP:29 asks for this to exist from the start rather than be retrofitted.

Functions

check_component

Whether one path component is acceptable as-is.

file_identity

filesystem_anchors

See the Windows variant: one root, and everything hangs below it.

is_out_of_space

Whether err reports that the filesystem has run out of space.

remove_entry

Remove one filesystem entry, choosing the syscall a symlink actually needs.