c-toggle-auto-newline is an interactive compiled Lisp function in `cc-cmds.el'.

(c-toggle-auto-newline &optional ARG)

Toggle auto-newline feature.
Optional numeric ARG, if supplied, turns on auto-newline when
positive, turns it off when negative, and just toggles it when zero or
left out.

Turning on auto-newline automatically enables electric indentation.

When the auto-newline feature is enabled (indicated by "/la" on the
mode line after the mode name) newlines are automatically inserted
after special characters such as brace, comma, semi-colon, and colon.