message: sleep and usleep
diff: extern crate platform;
  pub use platform::types::*;
  +use core::ptr;
  pub const R_OK: c_int = 1;
  pub const W_OK: c_int = 2;
  @@ -381,7 +382,13 @@ pub extern "C" fn setuid(uid: uid_t) -> c_int {
  #[no_mangle]
  pub extern "C" fn sleep(seconds: c_uint) -> c_uint {
  - unimplemented!();
  + let rqtp = timespec {
  + tv_sec: seconds as i64,
  + tv_nsec: 0,
  + };
  + let rmtp = ptr::null_mut();
  + platform::nanosleep(&rqtp, rmtp);
  + 0
  }
  #[no_mangle]
  @@ -441,7 +448,12 @@ pub extern "C" fn unlink(path: *const c_char) -> c_int {
  #[no_mangle]
  pub extern "C" fn usleep(useconds: useconds_t) -> c_int {
  - unimplemented!();
  + let rqtp = timespec {
  + tv_sec: 0,
  + tv_nsec: (useconds * 1000).into(),
  + };
  + let rmtp = ptr::null_mut();
  + platform::nanosleep(&rqtp, rmtp)
  }
  #[no_mangle]
  