With a temporary hack to limit the stack size for COM32 programs to 4
MB, I've successfully loaded tomsrtbt, a gPXE script loading tomsrtbt, a COMBOOT program, and another COM32 program from menu.c32. This works under QEMU as well as real hardware, so hopefully with a bit of progress on umalloc, I will be able to get rid of the hack and have this work correctly everywhere. Anyway, menu.c32 seems to be working properly with this hack applied, even though it calls some unimplemented COMBOOT
API functions; I will have to check what these functions are and whether it's worthwhile to implement them (or at least stub them), but for now, it's working fine, so I think I've nearly reached a big landmark (working menu support).