Specify how arguments are to be completed by Readline.
    
    For each NAME, specify how arguments are to be completed.  If no options
    are supplied, existing completion specifications are printed in a way that
    allows them to be reused as input.
    
    Options:
      -p	print existing completion specifications in a reusable format
      -r	remove a completion specification for each NAME, or, if no
    	NAMEs are supplied, all completion specifications
      -D	apply the completions and actions as the default for commands
    	without any specific completion defined
      -E	apply the completions and actions to "empty" commands --
    	completion attempted on a blank line
    
    When completion is attempted, the actions are applied in the order the
    uppercase-letter options are listed above.  The -D option takes
    precedence over -E.
    
    Exit Status:
    Returns success unless an invalid option is supplied or an error occurs.