Gets the time zone label and offset from GMT, using the TDF
    contained in the input utc.

    Format

      #include <utc.h>

      int utc_anyzone(tzname, tzlen, *tdf, isdst, *utc)

         char tzname;
         size_t tzlen;
         long *tdf;
         int *isdst;
         const utc_t *utc;