Start an external process on mac with c#

What you need to do is use the full path to the actual executable file. On OSX, the "apps" are actually specially structured folders with a .app extension, and the executable (generally) lives under Content/MacOS/[name].

For example, to open the Terminal:

System.Diagnostics.Process.Start("/Applications/Utilities/Terminal.app/Contents/MacOS/Terminal");

Or for TextEdit:

System.Diagnostics.Process.Start("/Applications/TextEdit.app/Contents/MacOS/TextEdit");

To locate the executable, you can right-click (or control-click) an app, and select Show Package Contents, and that will open up the actual folder in Finder. You can then navigate to the Contents/MacOS folder to find the actual executable.

To run your Mono executables, you have to use the full path to the mono executable and pass your program as an argument. Usually it will be something like /usr/local/bin/mono or possibly /usr/bin/mono.

For example:

System.Diagnostics.Process.Start("/usr/bin/local/mono /Users/Ilya/Projects/SomeApp.exe");

Obviously you'd use the actual path to your .exe file, the above is just an example.