- Electron version: 1.1.0
- Operating system: Windows
- Use case: cleanup and reporting tasks executed on quit (headless), which may take time and should not prevent from opening a new instance.
- Proposed solutions:
  - new _app.releaseSingleInstance()_ API which free the singleInstance lock
  - replace _app.releaseSingleInstance()_ API by an event listener (which may be listened/unlistened)
  - [app.makeSingleInstance](https://github.com/electron/electron/blob/master/docs/api/app.md#appmakesingleinstancecallback) returns the result of the callback function. So we can choose to quit or not in a more accurate way.
  - Provide a communication channel between the new instance and the main one (in callback arguments)

atom/browser/api/atom_api_app.cc
if (name == "appData")
    return brightray::DIR_APP_DATA;
  else if (name == "userData")
    return brightray::DIR_USER_DATA;
  else if (name == "cache")
    return brightray::DIR_CACHE;
  else if (name == "userCache")
    return brightray::DIR_USER_CACHE;
  else if (name == "home")
    return base::DIR_HOME;
  else if (name == "temp")
    return base::DIR_TEMP;
  else if (name == "userDesktop" || name == "desktop")
    return base::DIR_USER_DESKTOP;
  else if (name == "exe")
    return base::FILE_EXE;
  else if (name == "module")
    return base::FILE_MODULE;