Made by following https://www.youtube.com/watch?v=wLXIWKUWpSs

How-to

Prerequisites:

nasm - sudo apt install nasm

To assemble into machine code use:

nasm -f elf32 ex1.asm -u ex1.o

• elf - executable and linking format ELF is the executable format used by Linux.

To build an executable from the object file:

ld -m elf_i386 ex1.o -o ex1

To run the program:

./ex1

To check for exit status:

echo $?

https://stackoverflow.com/questions/6834487/what-is-the-dollar-question-mark-variable-in-shell-scripting