Supported architectures and ARCH variable?

[kuiperzone]

I'd like to confirm that appimagetool detects the architecture of supplied binaries automatically?

I understand that the architecture may be supplied as ARCH environment variable (i.e. as "x86_64" etc). If correct, do we have a list of recognised values?

[TheAssassin]

It does. Every appimagetool ships with a single runtime only, though. You can't build an AppImage for aarch64 with the x86_64 AppImage. If you provide the right runtime (there's a parameter for appimagetool), you can build an aarch64 AppImage on a x86_64 machine using the x86_64 AppImage.

Typically, nobody does that, though. For instance, our aarch64 AppImages are built in a suitable environment from start to end. There is no reason to build the AppImage on a different architecture. Not even when using qemu-user's binfmt_misc integration to seamlessly use QEMU to run binaries built for architectures the native CPU can't work with.