Function unregister

crates/stdlib/src/faulthandler.rs:1171–1183

(signum: i32, vm: &VirtualMachine)

    #[cfg(unix)]
    #[pyfunction]
    fn unregister(signum: i32, vm: &VirtualMachine) -> PyResult<bool> {
        check_signum(signum, vm)?;

        if let Some(old) = user_signals::clear_user_signal(signum as usize) {
            // Restore previous handler
            unsafe {
                libc::sigaction(signum, &old.previous, core::ptr::null_mut());
            }
            Ok(true)
        } else {
            Ok(false)
        }
    }

    // Test functions for faulthandler testing