diff --git a/include/ucore/clock.h b/include/ucore/clock.h
index 45adf32..1ec4c0d 100644
--- a/include/ucore/clock.h
+++ b/include/ucore/clock.h
@@ -23,6 +23,12 @@ struct UCoreClock {
     void (*now)(struct UCoreClock *clock, struct timeval *tv);
 };
 
+/** Convenience macro for geting the time from a UCoreClock
+ * @param uclock pointer to the clock
+ * @param tv struct timeval pointer that will be filled in.
+ */
+#define UCORE_CLOCK_NOW(uclock, tv) (uclock)->now((uclock), (tv))
+
 
 /** A cached clock where clock.now() returns
  * the cached value. The cache is updated
@@ -34,7 +40,7 @@ struct UCoreCachedClock {
     struct UCoreClock clock;
     /** The underlying real clock*/
     struct UCoreClock *real_clock;
-    /** cached value */
+    /** Cached value */
     struct timeval cache;
 };
 
@@ -45,7 +51,6 @@ struct UCoreCachedClock {
 struct UCoreSettableClock {
     /** The clock*/
     struct UCoreClock clock;
-    /** The underlying real clock*/
     /** Current value */
     struct timeval now;
 };
@@ -62,9 +67,13 @@ extern struct UCoreClock uc_timeofday_clock;
 extern struct UCoreClock uc_time_clock;
 
 /**
- * Initialize a cached clock where now() calls time().
- * This clock will this just have seconds resolution.
- * @param clock clock to initialize
+ * Initialize a cached clock whose now() is a cached
+ * value of the real_clock.
+ *
+ * @param uclock clock to initialize
+ * @param real_clock underlying clock that updates
+ *          the cache.
+ *        
  */
 void uc_cached_clock_init(struct UCoreCachedClock *uclock, 
                                 struct UCoreClock *real_clock);
@@ -75,9 +84,10 @@ void uc_cached_clock_update(struct UCoreCachedClock *uclock);
 
 
 /**
- * Initialize a user settable where now() calls time().
- * This clock will this just have seconds resolution.
- * @param clock clock to initialize
+ * Initialize a user settable clock, where now()
+ * returns the user set time.
+ *
+ * @param clock uclock to initialize
  */
 void uc_settable_clock_init(struct UCoreSettableClock *uclock);
 
@@ -88,7 +98,7 @@ void uc_settable_clock_set_tv(struct UCoreSettableClock *uclock,
                                 const struct timeval *tv);
 
 /**
- * Set the new timeval this clock will return
+ * Set the new time this clock will return
  * Convenience function that takes seconds/microseconds as arguments
  * instead of a struct timeval.
  **/