To complete a file or directory name press the TAB key.
$ ls -l on<TAB>line_help
If the filename is not completed enter more characters until the filename can be uniquely identified.
Directories are shown by the trailing / character.
To list all possible names of files type ESC-?. (Press and hold down the ESC key and type a ? (question mark)).
$ ls co<ESC><?>commands.xdh concepts.xdh conventions/ conver_man/ % ls co
Directories are shown by the trailing / character.