38 lines
912 B
ArmAsm
38 lines
912 B
ArmAsm
|
#PURPOSE: Simple program that exits and returns a
|
||
|
|
# status code back to the Linux kernel
|
||
|
|
#
|
||
|
|
|
||
|
|
#INPUT: none
|
||
|
|
#
|
||
|
|
|
||
|
|
#OUTPUT: returns a status code This can be viewed
|
||
|
|
# by typing
|
||
|
|
#
|
||
|
|
# echo $?
|
||
|
|
#
|
||
|
|
# after running the program
|
||
|
|
#
|
||
|
|
|
||
|
|
#VARIABLES:
|
||
|
|
# %rax holds the system call number
|
||
|
|
# %rbx holds the return status
|
||
|
|
#
|
||
|
|
.section .data
|
||
|
|
|
||
|
|
.section .text
|
||
|
|
.globl _start
|
||
|
|
|
||
|
|
_start:
|
||
|
|
mov $1, %rax # this is the linux kernel command
|
||
|
|
# number (system call) for exiting
|
||
|
|
# $ means immediate mode addressing,
|
||
|
|
# without $ it defaults to direct
|
||
|
|
# mode, looking up a number in
|
||
|
|
# address 1
|
||
|
|
|
||
|
|
mov $0, %rbx # this is the status number we will
|
||
|
|
# return to the OS
|
||
|
|
|
||
|
|
int $0x80 # this wakes up the kernel to run the
|
||
|
|
# exit command
|