-#define PPP_ALLSTATIONS 0xff /* All-Stations broadcast address */
-#define PPP_UI 0x03 /* Unnumbered Information */
-#define PPP_FLAG 0x7e /* Flag Sequence */
-#define PPP_ESCAPE 0x7d /* Asynchronous Control Escape */
-#define PPP_TRANS 0x20 /* Asynchronous transparency modifier */
+/*
+ * Bit definitions for flags.
+ */
+#define SC_COMP_PROT 0x00000001 /* protocol compression (output) */
+#define SC_COMP_AC 0x00000002 /* header compression (output) */
+#define SC_COMP_TCP 0x00000004 /* TCP (VJ) compression (output) */
+#define SC_NO_TCP_CCID 0x00000008 /* disable VJ connection-id comp. */
+#define SC_REJ_COMP_AC 0x00000010 /* reject adrs/ctrl comp. on input */
+#define SC_REJ_COMP_TCP 0x00000020 /* reject TCP (VJ) comp. on input */
+#define SC_CCP_OPEN 0x00000040 /* Look at CCP packets */
+#define SC_CCP_UP 0x00000080 /* May send/recv compressed packets */
+#define SC_DEBUG 0x00010000 /* enable debug messages */
+#define SC_LOG_INPKT 0x00020000 /* log contents of good pkts recvd */
+#define SC_LOG_OUTPKT 0x00040000 /* log contents of pkts sent */
+#define SC_LOG_RAWIN 0x00080000 /* log all chars received */
+#define SC_LOG_FLUSH 0x00100000 /* log all chars flushed */
+#define SC_RCV_B7_0 0x01000000 /* have rcvd char with bit 7 = 0 */
+#define SC_RCV_B7_1 0x02000000 /* have rcvd char with bit 7 = 1 */
+#define SC_RCV_EVNP 0x04000000 /* have rcvd char with even parity */
+#define SC_RCV_ODDP 0x08000000 /* have rcvd char with odd parity */
+#define SC_MASK 0x0fff00ff /* bits that user can change */