Function exit

pub fn exit(code: i32) -> !

Terminates the current process with the specified exit code.

This function will never return and will immediately terminate the current process. The exit code is passed through to the underlying OS and will be available for consumption by another process.

Note that because this function never returns, and that it terminates the process, no destructors on the current stack or any other thread’s stack will be run. If a clean shutdown is needed it is recommended to only call this function at a known point where there are no more destructors left to run; or, preferably, simply return a type implementing Termination (such as ExitCode or Result) from the main function and avoid this function altogether:

fn main() -> Result<(), MyError> {
    // ...
    Ok(())
}

In its current implementation, this function will execute exit handlers registered with atexit as well as other platform-specific exit handlers (e.g. fini sections of ELF shared objects). This means that Rust requires that all exit handlers are safe to execute at any time. In particular, if an exit handler cleans up some state that might be concurrently accessed by other threads, it is required that the exit handler performs suitable synchronization with those threads. (The alternative to this requirement would be to not run exit handlers at all, which is considered undesirable. Note that returning from main also calls exit, so making exit an unsafe operation is not an option.)

Platform-specific behavior

Unix: On Unix-like platforms, it is unlikely that all 32 bits of exit will be visible to a parent process inspecting the exit code. On most Unix-like platforms, only the eight least-significant bits are considered.

For example, the exit code for this example will be 0 on Linux, but 256 on Windows:

use std::process;

process::exit(0x0100);