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 CTRL-D. (Press and hold down the CTRL key and type a D.
ls co<CTRL-D> commands.xdh concepts.xdh conventions/ conver_man/ ls co
Directories are shown by the trailing / character.