2009-09-06 Linux assembler open file

sys_read equ 3
sys_write equ 4
sys_open equ 5
sys_close equ 6
o_rdonly equ 0
 
format ELF executable
segment readable executable
start:
    ;int fid = open("file.txt",O_RDONLY);
    mov eax, sys_open
    mov ebx, f
    mov ecx, o_rdonly
    int 80h
    mov dword [f_id], eax
    
 
    ;read( fid , &buf[0] , 12 );
    mov ebx, eax    
    mov eax, sys_read
    mov ecx, f_buf
    mov edx, f_buf_len
    int 80h
 
    ;write( 1 , &buf[0] , 12 );
    mov eax, sys_write
    mov ebx, 1
    mov ecx, f_buf
    mov edx, f_buf_len
    int 80h
 
    ;close( fid );
    mov eax, sys_close
    mov ebx, dword [f_id]
    int 80h
 
    mov eax , 1
    xor ebx, ebx
    int 80h			;system interupt
 
segment readable writeable
	f db "file.txt",0
	f_len = $-f
	f_buf db 12 dup 0
	f_buf_len = $-f_buf
	f_id dd 0

#include <fcntl.h>
 
int main()
{
	int fid = open("file.txt",O_RDONLY);
	char buf[12];
	read( fid , &buf[0] , 12 );
	write( 1 , &buf[0] , 12 );
	close( fid );
	return 0;
}