> In this specific case, it really is a user-land problem. a.out isnt even supported in new Linux kernels so how is that a user land problem? And you then repe

> In this specific case, it really is a user-land problem. a.out isnt even supported in new Linux kernels so how is that a user land problem? And you then repeated my point about how it’s not a user land problem by describing how it works as an ELF. ;) > These cases aren't equivalent. COM and MZ are 16-bit executables for MS-DOS [3], NE is for 16-bit Windows ; all can be officially run without workarounds on 32-bit x86 Windows systems (NTVDM has admittedly spotty compatibility, but the point stands). Here, we're talking about 32-bit x86 code, so COM/MZ/NE does not apply here (to my knowledge there never has been 16-bit Linux programs anyways). You’re not listening to what I’m saying. COM and a.out are equivalent because they’re raw formats. Even on 32 bit NT systems COM required emulation. The problem is the file formats are more akin to raw machine code than they are a modern container format. So yeah, one is 16 and the other 32bit but the problem you’re describing is related to the file format being unforgiving for different CPU architectures without emulation; and in many cases, disregarding the user land entirely. By your own admission, 32bit PEs and 32bit ELFs work perfectly fine on their respective Windows and Linux systems without any hacks. The difference here is that Windows ships WOW64 as part of the base install whereas mainstream Linux distributions doesn’t ship 32bit libraries as part of their base install. That doesn’t mean that you need hacks for 32bit though. For example on Arch it’s literally just one line in pacman.conf that you uncomment. My point was, if you wanted to ship a Linux distribution that supported random ELF binaries then you could. And package managers like Nix prove this fact. The reason it’s harder on Linux isn’t because it requires hacks. It’s because Linux has a completely different design for installing applications and thus backwards compatibility with random ELFs isn’t generally worth the effort. Also it’s really not fair to argue that a.out, a format that’s defined in the 70s and looong since deprecated across all unix-like systems is proof that Linux isn’t backwards compatible. ELF has been the primary file format for nearly 30 years on Linux now and a.out was only relatively recently fully removed from the kernel. Whereas COM has been problematic on Windows for the entirety of NT, including Windows 2000 and XP.