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I'm on Windows 11 in 64 bits and I wrote this code in assembly a64 but after being compiled and linked (with nasm and then ld) it just wait 3sec average and just stop :

bits 64

section .data
    message db 'Hello World !', 10

section .text
    global _start
    _start:
        mov rax, 1
        mov rdi, 1
        mov rsi, message
        mov rdx, 13+1
        syscall

        mov rax, 60
        mov rdi, 0
        syscall

nasm command typed in powershell : nasm -f win64 file.asm -o file.o

then ld command : ld file.o -o file.exe

When I start this file in powershell it just wait 3 sec and stop. Same for cmd.

It's a test program for my compiler to see if it works and I don't know if I didn't write correctly the code or if those compiler or linker don't work on Win 11.

Note : also my processsor is an Intel

Nixi
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2 Answers2

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  1. Windoze programs [generally] do not use syscall/sysenter; you usually use the WinAPI.
  2. Apart from adapting the “Hello World” referred to in David Wohlferd’s comment, you can meanwhile use the WSL, Windoh’s Subsystem for Linux, so you can still program with the familiar syscall interface. Obviously this requires an ‑felf64 executable to begin with, but (without having tried that out) something like wsl ‑‑exec myProgram should do the trick then.
  3. Some style comment: Filling rdx with 13+1 is prone to error. Use an equ constant instead.
Kai Burghardt
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Two possibilities: 1. "The linux syscalls are not going to work on Windows".

Try it on Linux.

2.syscall instruction use MSR regsisters as target.Traditional eax syscall-number will not work.

Try replace "syscall" with "int 0x80"

Please provide more infomation

AlanCui
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    1. Yes, this code is using Linux x86-64 system calls. 2. Huh? No. Windows doesn't even use `int 0x80` for system calls from user-space, that will just crash on the `int 0x80` instead of returning a "bad system call" error return. Windows x64 *does* use `syscall` for system calls, with RAX as the call number AFAIK (https://j00ru.vexillium.org/syscalls/nt/64/ / ), so the appropriate MSRs are set up, unlike the IDT entry for `0x80`. The call numbers [are undocumented and not stable between versions](//stackoverflow.com/q/2489889), and different from Linux; even the available calls differ. – Peter Cordes Feb 07 '22 at 11:03