Clarify description of GPS epoch.

1 files changed, 8 insertions, 8 deletions

diff --git a/gpsd.h-tail b/gpsd.h-tail
index 12012e91..f54b99fc 100644
--- a/gpsd.h-tail
+++ b/gpsd.h-tail
@@ -66,15 +66,15 @@ enum isgpsstat_t {
 #define MAX_PACKET_LENGTH	516	/* 7 + 506 + 3 */
 
 /*
- * 6 Jan 1981 00:00:00, second 0 of week 0 of the first rollover
- * period of GPS time.  The threshold value under which sytem clock
- * times are considered unreliable. Often, embedded systems come up
- * thinking it's early 1970 and the system clock will report small
- * positive values until the clock is set.  By choosing this as the
- * cutoff, we'll never reject historical GPS logs that are actually
- * valid.
+ * UTC of second 0 of week 0 of the first rollover period of GPS time.
+ * Used to compute UTC from GPS time. Also, the threshold value
+ * under which system clock times are considered unreliable. Often,
+ * embedded systems come up thinking it's early 1970 and the system
+ * clock will report small positive values until the clock is set.  By
+ * choosing this as the cutoff, we'll never reject historical GPS logs
+ * that are actually valid.
  */
-#define GPS_EPOCH	315964800
+#define GPS_EPOCH	315964800	/* 6 Jan 1981 00:00:00 UTC */
 
 struct gps_packet_t {
     /* packet-getter internals */