#define SP_BAD_FILTER 'B' /* error message for bad capture filter */
#define SP_PACKET_COUNT 'P' /* count of packets captured since last message */
#define SP_DROPS 'D' /* count of packets dropped in capture */
+#define SP_SUCCESS 'S' /* success indication, no extra data */
/*
* Win32 only: Indications sent out on the signal pipe (from parent to child)
* (UNIX-like sends signals for this)