Termination documentation should describe only the standard library runtime's use of Termination

[Lokathor]

The docs for the Termination are currently a little light. When the docs are expanded/updated as part of the stabilization the likely path forward is that they'll describe that a Termination returned from main will print any errors and then use std::process::exit to end the program.

When the Termination docs are expanded, we should be sure to maintain clearly that what the standard library's runtime does is not a hard requirement on what other runtimes must do with the Termination data. Particularly, a no_std binary being run on an embedded system does not necessarily have anywhere to print, and it certainly can't call the specific function std::process::exit.

• cc @yaahc

[ZHANGWENTAI]

@rustbot claim

[Dylan-DPC]

Closing this as it's solved by #95207