I realize this is almost identical to http://stackoverflow.com/questions/501290/windows-equivalent-of-the-mac-os-x-open-command and http://stackoverflow.com/questions/264395/linux-equivalent-of-the-mac-os-x-open-command, but I'm asking specifically about a command I can run in the Cygwin shell to use the current Windows UI application bound for the argument's extension, that as on OS X opens that application if necessary, and opens the specified file in that application.
The cmd.exe start command isn't an option in the Cygwin shell, nor are xdg-open or gnome-open available through Cygwin.
Is there an equivalent?