Updated documentation comments for DTrace probes.

The DTrace probes were not very clear about return type, so that was fixed.
While in there, I also fixed some typos/English things.

memcached_dtrace.d

@@ -22,31 +22,31 @@
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 provider memcached {
    /**
-    * Fired when a connection object is allocated from the connection pool
+    * Fired when a connection object is allocated from the connection pool.
     * @param connid the connection id
     */
    probe conn__allocate(int connid);
 
    /**
-    * Fired when a connection object is released back to the connection pool
+    * Fired when a connection object is released back to the connection pool.
     * @param connid the connection id
     */
    probe conn__release(int connid);
 
    /**
-    * Fired when a new connection object is being created (there is no more
-    * connection objects in the connection pool)
+    * Fired when a new connection object is created (there are no more
+    * connection objects in the connection pool).
     * @param ptr pointer to the connection object
     */
    probe conn__create(void *ptr);
 
    /**
-    * Fired when a connection object is being destroyed ("released back to
-    * the memory subsystem")
+    * Fired when a connection object is destroyed ("released back to
+    * the memory subsystem").
     * @param ptr pointer to the connection object
     */
    probe conn__destroy(void *ptr);
@@ -60,7 +60,7 @@ provider memcached {
    probe conn__dispatch(int connid, int threadid);
 
    /**
-    * Allocate memory from the slab allocator
+    * Allocate memory from the slab allocator.
     * @param size the requested size
     * @param slabclass the allocation will be fulfilled in this class
     * @param slabsize the size of each item in this class
@@ -69,26 +69,26 @@ provider memcached {
    probe slabs__allocate(int size, int slabclass, int slabsize, void* ptr);
 
    /**
-    * Failed to allocate memory (out of memory)
+    * Failed to allocate memory (out of memory).
     * @param size the requested size
     * @param slabclass the class that failed to fulfill the request
     */
    probe slabs__allocate__failed(int size, int slabclass);
 
    /**
-    * Fired when a slab class needs more space
+    * Fired when a slab class attempts to allocate more space.
     * @param slabclass class that needs more memory
     */
    probe slabs__slabclass__allocate(int slabclass);
 
    /**
-    * Failed to allocate memory (out of memory)
+    * Failed to allocate memory (out of memory).
     * @param slabclass the class that failed grab more memory
     */
    probe slabs__slabclass__allocate__failed(int slabclass);
 
    /**
-    * Release memory
+    * Release memory.
     * @param size the size of the memory
     * @param slabclass the class the memory belongs to
     * @param ptr pointer to the memory to release
@@ -102,63 +102,63 @@ provider memcached {
     * wasting cpu capacity.
     *
     * @param key the key searched for
-    * @param keylen lenght of the key
+    * @param keylen length of the key
     * @param depth the depth in the list of hash table
     */
    probe assoc__find(const char *key, int keylen, int depth);
 
    /**
     * Fired when a new item has been inserted.
     * @param key the key just inserted
-    * @param keylen lenght of the key
-    * @param nokeys the total number of keys currently being stored,
+    * @param keylen length of the key
+    * @param nokeys the total number of keys currently stored,
     *               including the key for which insert was called.
     */
    probe assoc__insert(const char *key, int keylen, int nokeys);
 
    /**
     * Fired when a new item has been removed.
     * @param key the key just deleted
-    * @param keylen lenght of the key
-    * @param nokeys the total number of keys currently being stored,
+    * @param keylen length of the key
+    * @param nokeys the total number of keys currently stored,
     *               excluding the key for which delete was called.
     */
    probe assoc__delete(const char *key, int keylen, int nokeys);
 
    /**
-    * Fired when an item is being linked in the cache
+    * Fired when an item is linked into the cache.
     * @param key the items key
-    * @param keylen lenght of the key
+    * @param keylen length of the key
     * @param size the size of the data
     */
    probe item__link(const char *key, int keylen, int size);
 
    /**
-    * Fired when an item is being deleted
+    * Fired when an item is deleted.
     * @param key the items key
-    * @param keylen lenght of the key
+    * @param keylen length of the key
     * @param size the size of the data
     */
    probe item__unlink(const char *key, int keylen, int size);
 
    /**
-    * Fired when the refcount for an item is reduced
+    * Fired when the refcount for an item is reduced.
     * @param key the items key
-    * @param keylen lenght of the key
+    * @param keylen length of the key
     * @param size the size of the data
     */
    probe item__remove(const char *key, int keylen, int size);
 
    /**
-    * Fired when the "last refenced" time is updated
+    * Fired when the "last refenced" time is updated.
     * @param key the items key
-    * @param keylen lenght of the key
+    * @param keylen length of the key
     * @param size the size of the data
     */
    probe item__update(const char *key, int keylen, int size);
 
    /**
-    * Fired when an item is bein replaced with another item
+    * Fired when an item is replaced with another item.
     * @param oldkey the key of the item to replace
     * @param oldkeylen the length of the old key
     * @param oldsize the size of the old item
@@ -170,15 +170,15 @@ provider memcached {
                        const char *newkey, int newkeylen, int newsize);
 
    /**
-    * Fired when the processing of a command starts
+    * Fired when the processing of a command starts.
     * @param connid the connection id
     * @param request the incomming request
     * @param size the size of the request
     */
    probe process__command__start(int connid, const void *request, int size);
 
    /**
-    * Fired when the processing of a command is done
+    * Fired when the processing of a command is done.
     * @param connid the connection id
     * @param respnse the response to send back to the client
     * @param size the size of the response
@@ -189,95 +189,100 @@ provider memcached {
     * Fired for a get-command
     * @param connid connection id
     * @param key requested key
-    * @param keylen lenght of the key
-    * @param size size of the key's data (or -1 if not found)
+    * @param keylen length of the key
+    * @param size size of the key's data (or signed int -1 if not found)
     * @param casid the casid for the item
     */
    probe command__get(int connid, const char *key, int keylen, int size, int64_t casid);
 
    /**
-    * Fired for a add-command
+    * Fired for an add-command.
     * @param connid connection id
     * @param key requested key
-    * @param keylen lenght of the key
-    * @param size the new size of the key's data (or -1 if not found)
+    * @param keylen length of the key
+    * @param size the new size of the key's data (or signed int -1 if
+    *             not found)
     * @param casid the casid for the item
     */
    probe command__add(int connid, const char *key, int keylen, int size, int64_t casid);
 
    /**
-    * Fired for a set-command
+    * Fired for a set-command.
     * @param connid connection id
     * @param key requested key
-    * @param keylen lenght of the key
-    * @param size the new size of the key's data (or -1 if not found)
+    * @param keylen length of the key
+    * @param size the new size of the key's data (or signed int -1 if
+    *             not found)
     * @param casid the casid for the item
     */
    probe command__set(int connid, const char *key, int keylen, int size, int64_t casid);
 
    /**
-    * Fired for a replace-command
+    * Fired for a replace-command.
     * @param connid connection id
     * @param key requested key
-    * @param keylen lenght of the key
-    * @param size the new size of the key's data (or -1 if not found)
+    * @param keylen length of the key
+    * @param size the new size of the key's data (or signed int -1 if
+    *             not found)
     * @param casid the casid for the item
     */
    probe command__replace(int connid, const char *key, int keylen, int size, int64_t casid);
 
    /**
-    * Fired for a prepend-command
+    * Fired for a prepend-command.
     * @param connid connection id
     * @param key requested key
-    * @param keylen lenght of the key
-    * @param size the new size of the key's data (or -1 if not found)
+    * @param keylen length of the key
+    * @param size the new size of the key's data (or signed int -1 if
+    *             not found)
     * @param casid the casid for the item
     */
    probe command__prepend(int connid, const char *key, int keylen, int size, int64_t casid);
 
    /**
-    * Fired for a append-command
+    * Fired for an append-command.
     * @param connid connection id
     * @param key requested key
-    * @param keylen lenght of the key
-    * @param size the new size of the key's data (or -1 if not found)
+    * @param keylen length of the key
+    * @param size the new size of the key's data (or signed int -1 if
+    *             not found)
     * @param casid the casid for the item
     */
    probe command__append(int connid, const char *key, int keylen, int size, int64_t casid);
 
    /**
-    * Fired for a cas-command
+    * Fired for a cas-command.
     * @param connid connection id
     * @param key requested key
-    * @param keylen lenght of the key
-    * @param size size of the key's data (or -1 if not found)
+    * @param keylen length of the key
+    * @param size size of the key's data (or signed int -1 if not found)
     * @param casid the cas id requested
     */
    probe command__cas(int connid, const char *key, int keylen, int size, int64_t casid);
 
    /**
-    * Fired for incr command
+    * Fired for an incr command.
     * @param connid connection id
     * @param key the requested key
-    * @param keylen lenght of the key
+    * @param keylen length of the key
     * @param val the new value
     */
    probe command__incr(int connid, const char *key, int keylen, int64_t val);
 
    /**
-    * Fired for decr command
+    * Fired for a decr command.
     * @param connid connection id
     * @param key the requested key
-    * @param keylen lenght of the key
+    * @param keylen length of the key
     * @param val the new value
     */
    probe command__decr(int connid, const char *key, int keylen, int64_t val);
 
    /**
-    * Fired for a delete command
+    * Fired for a delete command.
     * @param connid connection id
     * @param key the requested key
-    * @param keylen lenght of the key
+    * @param keylen length of the key
     */
    probe command__delete(int connid, const char *key, int keylen);