getcanonname
!getcanonname(hostbuf, size, true, NULL))
if (!getcanonname(hostbuf, size, true, NULL))
if (getcanonname(hbuf, sizeof(hbuf) - 1, !HasWildcardMX, &ttl))
getcanonname(mxhosts[0], sizeof(MXHostBuf) - 2, false, pttl))
(void) getcanonname(host, sizeof(host), !HasWildcardMX,
extern bool getcanonname __P((char *, int, bool, int *));