reader.asm

URL: https://mirkwood.cs.edinboro.edu/~bennett/class/cmsc3100/spring2026/notes/files/code/reader.asm

 
%include "CONSTANTS.h"

O_RDONLY equ 0
SYS_OPEN equ 2
SYS_CLOSE equ 3

section .data
     FileName: db `ocap.txt`,0
     ;FileName: db `afile`,0
     fd: dq 0
 
     stringLine: db `"%s"\n`,0;
      
section .bss
     newWord: resb 101

section .text

global main
main:
  
    mov rax, SYS_OPEN
    mov rdi, FileName
    mov rsi, O_RDONLY
    syscall

    mov [fd], rax

    mov rax, SYS_READ
    mov rdi, [fd]
    mov rsi, newWord
    mov rdx, 100
    syscall

    mov byte [newWord+rax-1], 0

    mov rdi, stringLine
    mov rsi, newWord
    call CallPrintf

    mov rax, SYS_CLOSE
    mov rdi, [fd] 
    syscall

    jmp Exit