+
+sub usage
+{
+ print << "XXX";
+
+ usage: watchdbg [-nnn lines before] [<regexp>|!<regexp>]...
+
+ You can have more than one <regexp> with an implicit 'and' between them. All
+ <regexes> are caseless. It's recommended to put 'not' (!<regex>) first in any list.
+ Don't forget that you are doing this in a shell and you may need to quote your
+ <regex>s.
+
+ watchdbg -2 progress
+
+ will display any line containing 'progress' and also the two lines before that.
+
+XXX
+}