Contrary to list.files(), this method guarantees to work
recursively. Moreover, when subdirectories are processed recursively,
directory names are also returned.
## S3 method for class 'default':
listDirectory(path=".", pattern=NULL, recursive=FALSE, allNames=FALSE, fullNames=FALSE,
...)character string of the filename pattern passed. See
list.files() for more details.TRUE, also files starting with a period are returned.TRUE, the full path names are returned.vector of file names.list.files() is used.