tramp-drop-volume-letter

tramp-drop-volume-letter is a compiled Lisp function in `tramp.el'.

(tramp-drop-volume-letter NAME)

Cut off unnecessary drive letter from file NAME.
The functions `tramp-*-handle-expand-file-name' call `expand-file-name'
locally on a remote file name. When the local system is a W32 system
but the remote system is Unix, this introduces a superfluous drive
letter into the file name. This function removes it.