dtor

crate	docs	version
ctor
dtor
link-section

Module teardown functions for Rust (like __attribute__((destructor)) in C/C++) for Linux, OSX, FreeBSD, NetBSD, Illumos, OpenBSD, DragonFlyBSD, Android, iOS, WASM, and Windows.

Examples

Print a message at shutdown time. Note that Rust may have shut down some stdlib services at this time.

#[dtor]
unsafe fn shutdown() {
    // Using println or eprintln here will panic as Rust has shut down
    libc::printf("Shutting down!\n\0".as_ptr() as *const i8);
}

Under the Hood

The #[dtor] macro effectively creates a constructor that calls libc::atexit with the provided function, ie roughly equivalent to:

#[ctor]
fn dtor_atexit() {
    libc::atexit(dtor);
}