Comment 11 for bug 1376716

I managed to build a version of acpioff available from the branch at https://github.com/awalls-cx18/syslinux/tree/acpi_off/com32/acpioff

Guess what? It works. Just install it as acpioff.c32 in your boot-resources directory and when you get stuck on the boot: prompt, just run it and it turns the machine off.

I am attaching here the built binary (syslinux is GPLv2, which AIUI implies his publically posted code would be as well).