Clarify ldns-read-zone -U and -u options

diff --git a/examples/ldns-read-zone.1 b/examples/ldns-read-zone.1
index c8ddfe1fd90f31f1faac4aa35fd753bf9012c168..68d717087abf13696e080f498c619f7007369eb1 100644 (file)
--- a/examples/ldns-read-zone.1
+++ b/examples/ldns-read-zone.1
@@ -60,13 +60,21 @@ will be skipped when printing the zone.
 
 .TP
 \fB-u\fR \fIRR type\fR
-Mark \fIRR type\fR for printing in unknown type format
+Mark \fIRR type\fR for printing in unknown type format.
+
+\fB-u\fR is not meant to be used together with \fB-U\fR.
 
 .TP
 \fB-U\fR \fIRR type\fR
 Mark \fIRR type\fR for \fBnot\fR printing in unknown type format.
-When only \fB-U\fR options are given, all types are printed in
-unknown type format except the given RR types
+
+The first occurrence of the \fB-U\fR option marks all RR types for printing
+in unknown type format except for the given \fIRR type\fR.
+Subsequent \fB-U\fR options will clear the mark for those \fIRR type\fRs too,
+so that only the given \fIRR type\fRs will be printed in the presentation 
+format specific for those \fIRR type\fRs.
+
+\fB-U\fR is not meant to be used together with \fB-u\fR.
 
 .TP
 \fB-v\fR

diff --git a/examples/ldns-read-zone.c b/examples/ldns-read-zone.c
index 0e3148d01027af137c6ab7669ec22f3a9ac74fa3..2793a79aa88e61af0c96e53e92a528088e673953 100644 (file)
--- a/examples/ldns-read-zone.c
+++ b/examples/ldns-read-zone.c
@@ -42,11 +42,19 @@ void print_usage(const char* progname)
                "\t\tnumber decrease, +1 is used in stead"
                        ".  (implies -s)\n");
        printf("\t-u <rr type>\n");
-       printf("\t\tMark <rr type> for printing in unknown type format\n");
+       printf("\t\tMark <rr type> for printing in unknown type format.\n");
+       printf("\t\tThis option may be given multiple times.\n");
+       printf("\t\t-u is not meant to be used together with -U.\n");
        printf("\t-U <rr type>\n");
        printf("\t\tMark <rr type> for not printing in unknown type format.\n");
-       printf("\t\tWhen only -U options are given, all types are printed in"
-               "\n\t\tunknown type format except the given RR types\n");
+       printf("\t\tThis option may be given multiple times.\n");
+       printf(
+       "\t\tThe first occurrence of the -U option marks all RR types for"
+       "\n\t\tprinting in unknown type format except for the given <rr type>."
+       "\n\t\tSubsequent -U options will clear the mark for those <rr type>s"
+       "\n\t\ttoo, so that only the given <rr type>s will be printed in the"
+       "\n\t\tpresentation format specific for those <rr type>s.\n");
+       printf("\t\t-U is not meant to be used together with -u.\n");
        printf("\t-v shows the version and exits\n");
        printf("\t-z sort the zone (implies -c).\n");
        printf("\nif no file is given standard input is read\n");