+?S:version_patchlevel_string:
+?S: This is a string combining version, subversion and
+?S: perl_patchlevel (if perl_patchlevel is non-zero).
+?S: It is typically something like
+?S: 'version 7 subversion 1' or
+?S: 'version 7 subversion 1 patchlevel 11224'
+?S: It is computed here to avoid duplication of code in myconfig.SH
+?S: and lib/Config.pm.
+?S:.