Add pthread_mutex_timedlock

Author: apasel422

src/unix/mod.rs

@@ -545,6 +545,8 @@ extern {
     pub fn pthread_mutex_lock(lock: *mut pthread_mutex_t) -> ::c_int;
     pub fn pthread_mutex_trylock(lock: *mut pthread_mutex_t) -> ::c_int;
     pub fn pthread_mutex_unlock(lock: *mut pthread_mutex_t) -> ::c_int;
+    pub fn pthread_mutex_timedlock(lock: *mut pthread_mutex_t,
+                                   abstime: *const ::timespec) -> ::c_int;
 
     pub fn pthread_mutexattr_init(attr: *mut pthread_mutexattr_t) -> ::c_int;
     #[cfg_attr(all(target_os = "macos", target_arch = "x86"),