ff-get-file-name
ff-get-file-name is a compiled Lisp function in `find-file.el
'.
(ff-get-file-name SEARCH-DIRS FNAME-STUB &optional SUFFIX-LIST)
Find a file in SEARCH-DIRS with the given name (or stub) FNAME-STUB.
If (optional) SUFFIX-LIST is nil, search for FNAME-STUB, otherwise
search for FNAME-STUB with each of the given suffixes. Return the
name of the first file found.