There were routines that were passed the
object name as an argument. Before the oextra
patch, ONAME() always returned a valid pointer
to a location within the obj struct. The oextra
patch worked around those cases by
using a temporary variable that was either set
to ONAME (if the obj passed the has_oname() test),
or to "" (pointer to an empty string) if no name was
present.
Since that might be a common thing to do, provide
the safe_oname() routine that you can use as a
function parameter without having to worry about
about whether ONAME(obj) is valid, and without
the need for the temporary variable.