typedef struct {
  signed char fname[80];  /* file name */
  signed char keytype;    /* key type ('C' Character,
                                       'L' Logical,
                                       'N' Date/Numeric) */
  signed char keylen;     /* key length */
  signed int exprlen;     /* key expression length */
  SC_FLAGS flags;         /* miscellaneous flags */
} SC_IDXINFO;