message: Use ptrace_getevent
  Using ptrace(PTRACE_GETEVENTMSG, ...) doesn't work with nix v0.9.0.
diff: use std::ptr;
  use nix::sys::signal::Signal;
  -use nix::sys::ptrace::{ptrace, ptrace_setoptions};
  +use nix::sys::ptrace::{ptrace, ptrace_getevent, ptrace_setoptions};
  use nix::sys::ptrace::ptrace::*;
  use nix::libc::{c_void, c_long};
  use nix::unistd::Pid;
  use nix::Result;
  -use std::mem;
  const RIP: u8 = 128;
  @@ -55,15 +54,6 @@ pub fn request_trace() -> Result<c_long> {
  }
  pub fn get_event_data(pid: Pid) -> Result<c_long> {
  - let data = Box::new(0u64 as c_long);
  - let temp: *mut c_void = unsafe { mem::transmute(data) };
  - let res = ptrace(PTRACE_GETEVENTMSG, pid, ptr::null_mut(), temp);
  - match res {
  - Ok(_) => {
  - let data: Box<c_long> = unsafe { mem::transmute(temp) };
  - Ok(*data)
  - },
  - err @ Err(..) => err,
  - }
  + ptrace_getevent(pid)
  }
  