Fix typos in comments and documentation.

include/nuttx/arch.h

@@ -399,21 +399,19 @@ void up_unblock_task(FAR struct tcb_s *tcb);
  * Name: up_block_task
  *
  * Description:
- *   The currently executing task at the head of
- *   the ready to run list must be stopped.  Save its context
- *   and move it to the inactive list specified by task_state.
+ *   The currently executing task at the head of the ready to run list must
+ *   be stopped.  Save its context and move it to the inactive list
+ *   specified by task_state.
  *
- *   This function is called only from the NuttX scheduling
- *   logic.  Interrupts will always be disabled when this
- *   function is called.
+ *   This function is called only from the NuttX scheduling logic.
+ *   Interrupts will always be disabled when this function is called.
  *
  * Input Parameters:
- *   tcb: Refers to a task in the ready-to-run list (normally
- *     the task at the head of the list).  It most be
- *     stopped, its context saved and moved into one of the
- *     waiting task lists.  It it was the task at the head
- *     of the ready-to-run list, then a context to the new
- *     ready to run task must be performed.
+ *   tcb: Refers to a task in the ready-to-run list (normally the task at
+ *     the head of the list).  It must be stopped, its context saved and
+ *     moved into one of the waiting task lists.  If it was the task at the
+ *     head of the ready-to-run list, then a context switch to the new ready
+ *     to run task must be performed.
  *   task_state: Specifies which waiting task list should be
  *     hold the blocked task TCB.
  *

include/nuttx/fs/fs.h

@@ -70,7 +70,7 @@
  *
  * This is only important when compiling libraries (libc or libnx) that are
  * used both by the OS (libkc.a and libknx.a) or by the applications
- * (libuc.a and libunx.a).  The that case, the correct interface must be
+ * (libuc.a and libunx.a).  In that case, the correct interface must be
  * used for the build context.
  *
  * REVISIT:  In the flat build, the same functions must be used both by

include/nuttx/mm/iob.h

@@ -269,7 +269,7 @@ FAR struct iob_s *iob_tryalloc(bool throttled, enum iob_user_e consumerid);
  * Name: iob_navail
  *
  * Description:
- *   Return the number of of available IOBs.
+ *   Return the number of available IOBs.
  *
  ****************************************************************************/
 

include/nuttx/mqueue.h

@@ -65,7 +65,7 @@
  *
  * This is only important when compiling libraries (libc or libnx) that are
  * used both by the OS (libkc.a and libknx.a) or by the applications
- * (libuc.a and libunx.a).  The that case, the correct interface must be
+ * (libuc.a and libunx.a).  In that case, the correct interface must be
  * used for the build context.
  *
  * REVISIT:  In the flat build, the same functions must be used both by

include/nuttx/net/net.h

@@ -67,7 +67,7 @@
  *
  * This is only important when compiling libraries (libc or libnx) that are
  * used both by the OS (libkc.a and libknx.a) or by the applications
- * (libuc.a and libunx.a).  The that case, the correct interface must be
+ * (libuc.a and libunx.a).  In that case, the correct interface must be
  * used for the build context.
  *
  * REVISIT:  In the flat build, the same functions must be used both by

include/nuttx/sched.h

@@ -156,7 +156,7 @@
  *
  * This is only important when compiling libraries (libc or libnx) that are
  * used both by the OS (libkc.a and libknx.a) or by the applications
- * (libuc.a and libunx.a).  The that case, the correct interface must be
+ * (libuc.a and libunx.a).  In that case, the correct interface must be
  * used for the build context.
  *
  * REVISIT:  In the flat build, the same functions must be used both by

include/nuttx/semaphore.h

@@ -66,7 +66,7 @@
  *
  * This is only important when compiling libraries (libc or libnx) that are
  * used both by the OS (libkc.a and libknx.a) or by the applications
- * (libuc.a and libunx.a).  The that case, the correct interface must be
+ * (libuc.a and libunx.a).  In that case, the correct interface must be
  * used for the build context.
  *
  * REVISIT:  In the flat build, the same functions must be used both by

include/nuttx/signal.h

@@ -81,7 +81,7 @@ struct sigwork_s
  *
  * This is only important when compiling libraries (libc or libnx) that are
  * used both by the OS (libkc.a and libknx.a) or by the applications
- * (libuc.a and libunx.a).  The that case, the correct interface must be
+ * (libuc.a and libunx.a).  In that case, the correct interface must be
  * used for the build context.
  *
  * REVISIT:  In the flat build, the same functions must be used both by

include/nuttx/timers/pwm.h

@@ -289,7 +289,7 @@ int pwm_register(FAR const char *path, FAR struct pwm_lowerhalf_s *dev);
  *      number of pulses is required, the 'count' value will be nonzero.
  *   2. The lower half driver's start() method must verify that it can
  *      support the request pulse train (frequency, duty, AND pulse count).
- *      It it cannot, it should return an error.  If the pulse count is
+ *      If it cannot, it should return an error.  If the pulse count is
  *      non-zero, it should set up the hardware for that number of pulses
  *      and return success.  NOTE:  That is CONFIG_PWM_PULSECOUNT is
  *      defined, the start() method receives an additional parameter

include/signal.h

@@ -256,7 +256,7 @@
 #  define SIGEV_THREAD  3 /* A notification function is called */
 #endif
 
-/* Special values of of sa_handler used by sigaction and sigset.  They are all
+/* Special values of sa_handler used by sigaction and sigset.  They are all
  * treated like NULL for now.  This is okay for SIG_DFL and SIG_IGN because
  * in NuttX, the default action for all signals is to ignore them.
  */