— Function: user-name-all-completions partial-username

This function returns a list of all possible completions for a user name starting with partial-username. The order of the completions is unpredictable and conveys no useful information.

The argument partial-username must be a partial user name containing no tilde character and no slash.

— Function: user-name-completion partial-username

This function completes a user name from partial-username. It returns the longest prefix common to all user names that start with partial-username.

If only one match exists and partial-username matches it exactly, the function returns t. The function returns nil if no user name starting with partial-username exists.

— Function: user-name-completion-1 partial-username

This function completes the partial user name partial-username, like user-name-completion, differing only in the return value. This function returns the cons of the completion returned by user-name-completion, and a boolean indicating whether that completion was unique.