workaround applications that daemonize and return after launch

[Antoine Martin]

Examples of problematic software:

• KDE apps
• open-office
• firefox
• chrome

For applications that cannot be launched multiple times (open-office, most browsers), it is unlikely that the solution will be perfect as it will probably still fail to launch more than once (as opening again only adds a new tab/view to these apps). In this case, we may want to detect that the application is already running and offer to resume it or at least notify the user.

For applications that can be launched multiple times, we may be able to use:

• ​systemd or just re-use some concepts (use of containers). The advantage of integrating with systemd would be the session management (we could hook dbus,cups,etc here), the downside is that this is Linux only (and not even available or installed everywhere) so we would still need a fallback.
• LD_LIBRARY tricks - no, don't want to go there.
• ​proc connector - again this is Linux specific. It is much more lightweight than systemd though. We would still have to wrap this in something, ideally integrate it with the twisted/gtk main loop. This is probably the easiest option, at least for experimenting.

[Antoine Martin]

This also happens when opening files remotely, r3533 improves things by avoiding xdg-open whenever possible (use xdg-mime and launch ourselves)