libthreads: make typedef for 'thread_id_t'

Just in case we need to change it later on, let's use it as a named type.

diff --git a/libthreads.h b/libthreads.h
index aa7faf44d255452c172e2db2cf40919e4453b555..9d290a7ddf12162ce67fa2a20294da4e4034cfb8 100644 (file)
--- a/libthreads.h
+++ b/libthreads.h
@@ -10,12 +10,14 @@ typedef enum thread_state {
        THREAD_COMPLETED
 } thread_state;
 
+typedef int thread_id_t;
+
 struct thread {
        void (*start_routine)();
        void *arg;
        ucontext_t context;
        void *stack;
-       int id;
+       thread_id_t id;
        thread_state state;
 };