dired-insert-subdir
dired-insert-subdir is an interactive autoloaded compiled Lisp function in `dired-aux.el
'.
(dired-insert-subdir DIRNAME &optional SWITCHES NO-ERROR-IF-NOT-DIR-P)
Insert this subdirectory into the same Dired buffer.
If it is already present, overwrite the previous entry;
otherwise, insert it at its natural place (as `ls -lR' would
have done).
With a prefix arg, you may edit the `ls' switches used for this listing.
You can add `R' to the switches to expand the whole tree starting at
this subdirectory.
This function takes some pains to conform to `ls -lR' output.