Some varnishtop -f coverage

bin/varnishtest/tests/u00004.vtc

@@ -15,6 +15,16 @@ client c1 {
 shell -expect "fetch" "varnishtop -n ${v1_name} -1"
 shell -expect "fetch" "varnishtop -n ${v1_name} -d"
 
+# without -f
+shell -match "1\\.00 RespHeader Date: [^\\n]+\\n" {
+	varnishtop -n ${v1_name} -1 -i RespHeader
+}
+
+# with -f
+shell -match "1\\.00 RespHeader Date\\n" {
+	varnishtop -n ${v1_name} -1 -f -i RespHeader
+}
+
 shell -match "Usage: .*varnishtop <options>" \
 	"varnishtop -h"
 shell -expect "Copyright (c) 2006 Verdens Gang AS" \

bin/varnishtop/varnishtop_options.h

@@ -40,7 +40,9 @@
 #define TOP_OPT_f							\
 	VOPT("f", "[-f]", "First field only",				\
 	    "Sort and group only on the first field of each log entry."	\
-	    " This is useful when displaying e.g. stataddr entries,"	\
+	    " For log entries in the form ``prefix: value`` it is the"	\
+	    " prefix without the colon that is sorted and grouped."	\
+	    " This is useful when displaying e.g. ReqStart entries,"	\
 	    " where the first field is the client IP address."		\
 	)