A few years back eclipse added an option where a file association could be added in the operating system between an extension and executable that can be used to open that file. 

In summary, user could double click on a file with a known extension and that file would be opened after eclipse starts. 

This functionality has never worked in ccstudio launcher. When trying a recent v9 build to test stock eclipse.exe launcher, it worked as expected. However, ccstudio launcher did not. When comparing the arguments being passed to VM between ccstudio and eclipse launchers, there is a string that is missing when ccstudio launcher is used.