|
CS 456 - Systems Programming
Spring 2024
|
Displaying ./code/asm/helloworld-input.asm
; Hello World Program (Getting input)
; Compile with: nasm -f elf helloworld-input.asm
; Link with (64 bit systems require elf_i386 option): ld -m elf_i386 helloworld-input.o -o helloworld-input
; Run with: ./helloworld-input
%include 'functions.asm'
SECTION .data
msg1 db 'Please enter your name: ', 0h ; message string asking user for input
msg2 db 'Hello, ', 0h ; message string to use after user has entered their name
SECTION .bss
sinput: resb 255 ; reserve a 255 byte space in memory for the users input string
SECTION .text
global _start
_start:
mov eax, msg1
call sprint
mov edx, 255 ; number of bytes to read
mov ecx, sinput ; reserved space to store our input (known as a buffer)
mov ebx, 0 ; read from the STDIN file
mov eax, 3 ; invoke SYS_READ (kernel opcode 3)
int 80h
mov eax, msg2
call sprint
mov eax, sinput ; move our buffer into eax (Note: input contains a linefeed)
call sprint ; call our print function
call quit
|