boredos_mirror/src/kernel/user_test.asm
2026-02-28 00:19:00 +01:00

25 lines
687 B
NASM

; Copyright (c) 2023-2026 Chris (boreddevnl)
; This software is released under the GNU General Public License v3.0. See LICENSE file for details.
; This header needs to maintain in any file it is present in, as per the GPL license terms.
global user_test_function
section .text
user_test_function:
; Syscall convention
.loop:
; Invoke SYS_WRITE (Syscall #1)
mov rdi, 1 ; arg1: fd = 1 (stdout)
lea rsi, [rel msg] ; arg2: buffer (RIP-relative)
mov rdx, 15 ; arg3: length
mov eax, 1 ; syscall_num = 1 (SYS_WRITE)
syscall
; Some delay loop
mov rcx, 100000000
.delay:
dec rcx
jnz .delay
jmp .loop
msg: db "Hello syscall!", 10