+ void *sc_devp; /* pointer to device-dependent structure */
+ int (*sc_start)(); /* start routine */
+ short sc_mru; /* max receive unit */
+ pid_t sc_xfer; /* used in xferring unit to another dev */
+ struct ifqueue sc_inq; /* TTY side input queue */
+ struct ifqueue sc_fastq; /* IP interactive output packet queue */
+#ifdef VJC
+ struct slcompress sc_comp; /* vjc control buffer */
+#endif
+ u_int sc_bytessent; /* count of octets sent */
+ u_int sc_bytesrcvd; /* count of octets received */
+ caddr_t sc_bpf; /* hook for BPF */
+
+ /* Device-dependent part for async lines. */
+ ext_accm sc_asyncmap; /* async control character map */
+ u_long sc_rasyncmap; /* receive async control char map */