From RetroArch website: RetroArch is a front-end for emulators, game engines and media players. Among other things, it enables you to run classic games on a wide range of computers and consoles through its slick graphical interface. Settings are also unified so configuration is done once and for all.
The software and its cores
retroarch : the main software.
libretro-* packages : these packages provide various emulators which can accessed through RetroArch. They are referred to as cores.
RetroArch in Debian does not come with every of the possible cores, which means some emulators are unavailable.
Since Debian package management handles the software updates, auto-update of the various components from within RetroArch has been disabled. Downloading new cores within RetroArch is also not working because it would write to a system restricted directory (that is: /usr/lib/x86_64-linux-gnu/libretro). See the patches applied, in particular to the RetroArch config file.
If you want to use other cores, you may set up another directory to store the cores.
Having these settings in ~/.config/retroarch/retroarch.conf should help:
libretro_directory = "~/.config/retroarch/libretro/" libretro_info_path = "~/.config/retroarch/libretro-info/" menu_show_core_updater = "true"
You should now be able to update the list of core informations, then download the cores of your choice. Take note not all listed cores are distributed under a DFSG compliant software license.
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