parent
32bc64e632
commit
d67c4c6ab0
2 changed files with 29 additions and 15 deletions
@ -1,21 +1,31 @@ |
|||||||
%include "config.asm" |
; hello.asm a first program for nasm for Linux, Intel, gcc |
||||||
|
; |
||||||
global main |
; assemble: nasm -f elf -l hello.lst hello.asm |
||||||
extern puts |
; link: gcc -o hello hello.o |
||||||
|
; run: hello |
||||||
|
; output is: Hello World |
||||||
|
|
||||||
section .data |
%include "config.asm" |
||||||
hi db 'Hello, World', 0 |
|
||||||
|
|
||||||
%ifdef FOO |
%ifdef FOO |
||||||
%define RETVAL HELLO |
%define RETVAL HELLO |
||||||
%endif |
%endif |
||||||
|
|
||||||
section .text |
SECTION .data ; data section |
||||||
main: |
msg: db "Hello World",10 ; the string to print, 10=cr |
||||||
push rbp |
len: equ $-msg ; "$" means "here" |
||||||
lea rdi, [rel hi] |
; len is a value, not an address |
||||||
call puts wrt ..plt |
|
||||||
pop rbp |
SECTION .text ; code section |
||||||
mov ebx,RETVAL |
global main ; make label available to linker |
||||||
mov eax,1 |
main: ; standard gcc entry point |
||||||
int 0x80 |
|
||||||
|
mov edx,len ; arg3, length of string to print |
||||||
|
mov ecx,msg ; arg2, pointer to string |
||||||
|
mov ebx,1 ; arg1, where to write, screen |
||||||
|
mov eax,4 ; write sysout command to int 80 hex |
||||||
|
int 0x80 ; interrupt 80 hex, call kernel |
||||||
|
|
||||||
|
mov ebx,RETVAL ; exit code, 0=normal |
||||||
|
mov eax,1 ; exit command to kernel |
||||||
|
int 0x80 ; interrupt 80 hex, call kernel |
||||||
|
Loading…
Reference in new issue