Items are separated by any number of blanks and/or tab characters. The port number and protocol name are considered a single item; a ``/'' is used to separate the port and protocol (for example, ``512/tcp''). A ``#'' indicates the beginning of a comment; subsequent characters up to the end of the line are not interpreted by the routines which search the file.
Service names may contain any printable character other than a field delimiter, newline, or comment character.
RFC 1340
SCO OpenServer Release 5.0.6 -- 1 August 2000