> Rust has no reason to touch the original Unix API.
As a systems language, Rust must provide access to the APIs of the underlying system, and on UNIX, that’s, well, UNIX.
As a systems language, Rust must provide access to the APIs of the underlying system, and on UNIX, that’s, well, UNIX.
Let me clarify. There is no reason for std::env to be dragged down by UNIX, it could be its own, modern, safe thing with the Unix API living in std::pet_cemetary or some comparably clear namespace for people who have to pass runtime information to a C library through absolutely unsafe ways. Environment variables are usefull, the unix limitations make them less so.
It could be a completely separate "modern, safe thing" which roughly nobody has any use for and which would be confusing since what people want are environment variables and this would instead be its own "modern, safe thing" for some reason.
Mutex<HashMap<String,String>> is probably a reasonable "modern, safe thing" for the handful of people who actually would get value out of this, and the fact it's not labelled "Environment variables" because that's not what it is probably also avoids people who needed the actual environment variables cursing because they were hidden down the back of the sofa.
Why not? Is it the lack of race conditions? The lack of crashes or memory leaks? Is it the fact that you came up with it in five seconds and it is still a million times better than what we have? Or is it the fact that the holy book of Posix spells out how to do it badly in C and because of that we are never allowed to replace it with something better?