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Comment by enriquto | Hacker News Reader

you can disassemble the code portion, they are single-byte instructions

    push 0x2a
    pop edi
    push 0x3c
    pop eax
    db 0x0f, 0x05 ; invalid?

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    ; set the first syscall argument to 42
    push   0x2a
    pop    edi

    ; select syscall 60 (sys_exit)
    push   0x3c
    pop    eax

    ; sys_exit(42)
    syscall

LOL my asm is rusty, didn't even know about the syscall instruction (I'd have used int 0x80 here)

What's the point of `push`ing constants to the stack and `pop`ing them to registers instead of `mov`ing them directly?

I think they encode smaller?

That's cool - I wonder why exit code is not set to 42 in practice? binary still returns 0, must be a bug somewhere.

A successful run not exiting with EXIT_SUCCESS usually requires a good reason to justify it.

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