--- a/perlgrok.pl	Thu Sep 30 15:30:10 2021 +0200
+++ b/perlgrok.pl	Thu Sep 30 15:38:43 2021 +0200
@@ -39,6 +39,7 @@
     "parsed=s"      => \$fn_parsed,
     "failed=s"      => \$fn_fail,
     "debug=i"       => \$DEBUG,
+    "retrace!"      => \$re_trace,
     "help"          => \$help,
 ) or die "error in command line arguments";
 
@@ -46,8 +47,15 @@
     my $VER = '$Id: perlgrok.pl,v d6e64daafdc1 2021/09/29 23:46:59 grin $';
     print "$0 $VER (c) Peter 'grin' Gervai, 2021\n\n";
     print "Usage: $0 [--input input_file] [--pattern pattern_file] [--pattern another] [--top final_macro] \n";
-    print "          [--parsed parsed_outfile] [--failed failed_lines_file] [--debug n] [--help]\n";
-    print "       defaults are stdin, stdout, 'patterns' as patternfile and 'TEST' as final macro.\n\n";
+    print "          [--parsed parsed_outfile] [--failed failed_lines_file] [--debug n] [--noretrace] [--help]\n";
+    print "        input:   input file to be processed; default stdin\n";
+    print "        pattern: input grok-style pattern file; default patterns (name space pattern) (multiple possible)\n";
+    print "        top:     name of the pattern to match; default TEST\n";
+    print "        parsed:  output filename for parsed data; default stdout\n";
+    print "        failed:  output filename for lines not matched; default none\n";
+    print "        debug:   debug level 0 (none), 1 (error), 3 (warning), 7 (debug), 9 (trace)\n";
+    print "        notrace: disable regexp syntax check per pattern\n";
+    print "\n\n";
     exit;
 }