Make the -h output include a list of compiled-in drivers.

1 files changed, 8 insertions, 2 deletions

diff --git a/gpsd.c b/gpsd.c
index 5ffd6773..39d6da5a 100644
--- a/gpsd.c
+++ b/gpsd.c
@@ -196,6 +196,8 @@ void gpsd_report(int errlevel, const char *fmt, ... )
 
 static void usage(void)
 {
+    struct gps_type_t **dp;
+
     (void)printf("usage: gpsd [-b] [-n] [-N] [-D n] [-F sockfile] [-P pidfile] [-S port] [-h] device...\n\
   Options include: \n\
   -b		     	    = bluetooth-safe: open data sources read-only\n\
@@ -209,9 +211,13 @@ static void usage(void)
   -V			    = emit version and exit.\n\
 A device may be a local serial device for GPS input, or a URL of the form:\n\
      [{dgpsip|ntrip}://][user:passwd@]host[:port][/stream]\n\
-in which case it specifies an input source for DGPS or ntrip data.\n",
-
+in which case it specifies an input source for DGPS or ntrip data.\n\
+\n\
+The following driver types are compiled into this gpsd instance:\n",
 	   DEFAULT_GPSD_PORT);
+    for (dp = gpsd_drivers; *dp; dp++) {
+	(void)printf("    %s\n", (*dp)->typename);
+    }
 }
 
 static int passivesock(char *service, char *protocol, int qlen)