I believe there is no way to specify values with leading "-" in regtool. I expect the same applies to keys. An "end of switch processing" switch would be useful, forcing 'regtool' to interpret all remaining arguments literally.
Example: % regtool -s set '\HKCU\Environment\MAVEN_OPTS' "-Xms512m -Xmx3072m -Dcom.sun.management.jmxremote" regtool: unknown option -- X Try `regtool --help' for more information. % regtool --version regtool (cygwin) 2.11.1 Registry tool Copyright (C) 2000 - 2018 Cygwin Authors Thanks, ggrimes -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
