How can I reset the environment to the default for a user when running program as that user?

Question

I'm trying to run a program in Rust using libc as another user.

nix::unistd::setuid(uid).unwrap();

If I fork and exec a process which runs printenv , the environment does not change. How can I reset the environment to the default for a user?

Answer 1

With nix::unistd::execve() 's third argument env , you have full control over the next processes environment. Also see exec(3) .