Well, sure, but the usermod method I was remarking on isn't standard either, and it established a Linux context for this thread. I'm not sure there's a truly portable way to lock a password across SysV, Linux, and BSD systems.
The _effect_ of what you do (make an "impossible hash") is the way, as far as I know -- whether its vipw, passwd -l, whatever...
Regardless -- I'm not trying to diminish your solution, nor Linux; I elided over the usermod example in the grandparent (didn't recognize it at all), but interestingly, as I look on my NetBSD system,there is a usermod(8), with a -p for already hashed passwords. As I test it though, it rejects '!' as an argument:
