exit-code.gnu.asm


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/*
 * This file was a very early example, written by consulting [1]. It was
 * useful primarily to see how the GNU assembler handles these opcodes, to
 * better understand the encoding.
 *
 * [1] https://www.muppetlabs.com/~breadbox/software/tiny/teensy.html
 *
 *
 * gcc -o exit-code -nostartfiles -nostdlib exit-code.gnu.asm && ./exit-code ; echo $?
 *
 * or
 *
 * as -o exit-code.o exit-code.gnu.asm && ld -s -o exit-code exit-code.o && ./exit-code; echo $?
 *
 * Can't use nasm, nasm is 32-bit only.
 *
 * Since you get a nice clean file, you can then do:
 *
 * objdump --disassemble exit-code
 */
.text

.global _start

_start:
        mov $60, %eax
        mov $42, %edi
        syscall