It's so great to have a standard like POSIX...

locations of explicit_bzero by platform:

linux: string.h if __USE_MISC is defined
freebsd: strings.hif __BSD_VISIBLE is defined
openbsd: string.h if __BSD_VISIBLE is defined
haiku: bsd/string.h
alpine: string.h if _GNU_SOURCE or _BSD_SOURCE is defined

macOS doesn't appear to have it, anyone know what to use?

On windows we'll be using SecureZeroMemory.

Any other os's i'm missing?