You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: vlock.rs
    path of file: ./repos/rustybox/loginutils
    
    the code of the file until where you have to start completion: use crate::librb::signal::__sighandler_t;
use libc;
use lib
    
unsafe extern "C" fn release_vt(mut _signo: libc::c_int) {
  /* If -a, param is 0, which means:
   * "no, kernel, we don't allow console switch away from us!" */
  ioctl(
    0,
    0x5605i32 as libc::c_ulong,
    (option_mask32 == 0) as libc::c_int as libc::c_ulong,
  );
}