Run will allow execution of a console mode GUI program without its attendant console appearing. This includes cygwin applications such as rxvt and xterm, along with the cygwin version of XEmacs 21.0 and the native version of XEmacs 21.0. In fact, this program is based on the runemacs.exe that comes with that distribution of XEmacs.
For more info, see the README
Many un*x programs are written as "console mode" applications, even if they pop open their own windows. For example, rxvt (a popular un*x-style terminal window) creates a window in which you can run a un*x shell. However, when you run rxvt, it takes over your current command window, until you close the rxvt window. Under most Unixen, the way around this is to execute the rxvt program in the background, like this:
rxvt &
Unfortunately, this doesn't work from a dos-box under W*ndows. Also, what if you want to create a shortcut to rxvt, so that you can double-click the icon on your desktop? Well, if you try this, you will not only get an rxvt window, but you will also get a second window - a dummy dos-box. You can't use this dos-box, you can't close it (or you'll lose your rxvt window). All it does it take up screen space, or taskbar space if you minimize it. This same argument goes for both the cygwin port of XEmacs, and the native port of XEmacs.
run.exe will create a hidden dos-box, that doesn't show up on the desktop OR on the taskbar. It will then execute your program, and pass along any extra arguments. This way,