SYNOPSIS
        string traceprefix(string prefix)
        string traceprefix(int dummy)

DESCRIPTION
        If called with a string, only objects matching this prefix will
        be traced. The string must not contain a leading "/" because
        the object names are stored internally without it. If called
        with a number, the traceprefix will be ignored and all objects
        will be traced. Returns the last traceprefix or 0 if there
        wasn't any.

        The master-lfun valid_trace() is called with "traceprefix"
        as argument to verify the use of this efun.

EXAMPLE
        object obj;
        string prefix;
        obj = find_player("deepthought");
        prefix = file_name(obj);
        prefix = prefix[1..strlen(prefix)-1]; /* cut off the leading "/" */
        traceprefix(prefix);
          /* From here on, only code in the object "std/player#69"
           * will be traced.
           */
        trace(1|2|4|8);
        ...
        trace(0);

SEE ALSO
        trace(E)
