Update TODO, cosmetic changes, spelling -- US English spells it canceled and canceling vs cancelled and cancelling. No idea why.

TODO

@@ -595,34 +595,34 @@ o pthreads (sched/pthreads)
                the following functions.  There are some execptions as noted:
 
                 accept()             mq_timedsend()           NA putpmsg()          sigtimedwait()
-             -4 aio_suspend()     NA msgrcv()                    pwrite()        NA sigwait()
+             04 aio_suspend()     NA msgrcv()                    pwrite()        NA sigwait()
              NA clock_nanosleep() NA msgsnd()                    read()             sigwaitinfo()
-                close()           NA msync()                  NA readv()         -1 sleep()
+                close()           NA msync()                  NA readv()         01 sleep()
-                connect()            nanosleep()                 recv()          -2 system()
+                connect()            nanosleep()                 recv()          02 system()
-             OK creat()              open()                      recvfrom()      NA tcdrain()
+             -- creat()              open()                      recvfrom()      NA tcdrain()
-                fcntl()              pause()                  NA recvmsg()       -1 usleep()
+                fcntl()              pause()                  NA recvmsg()       01 usleep()
-             NA fdatasync()          poll()                      select()        OK wait()
+             NA fdatasync()          poll()                      select()        -- wait()
                 fsync()              pread()                     sem_timedwait()    waitid()
              NA getmsg()          NA pselect()                   sem_wait()         waitpid()
              NA getpmsg()            pthread_cond_timedwait()    send()             write()
              NA lockf()              pthread_cond_wait()      NA sendmsg()       NA writev()
                 mq_receive()         pthread_join()              sendto()
-                mq_send()            pthread_testcancel()     -3 sigpause()
+                mq_send()            pthread_testcancel()     03 sigpause()
                 mq_timedreceive() NA putmsg()                    sigsuspend()
 
-               NA Not supported
+                  NA Not supported
-               OK Doesn't need instrumentation.  Handled by lower level calls.
+                  -- Doesn't need instrumentation.  Handled by lower level calls.
-               -n See note n
+                  nn See note nn
 
-               NOTE 1: sleep() and usleep() are user-space functions in the C library and cannot
+               NOTE 01: sleep() and usleep() are user-space functions in the C library and cannot
                serve as cancellation points.  They are, however, simple wrappers around nanosleep
                which is a true cancellation point.
-               NOTE 2: system() is actually implemented in apps/ as part of NSH.  It cannot be
+               NOTE 02: system() is actually implemented in apps/ as part of NSH.  It cannot be
                a cancellation point either.
-               NOTE 3: sigpause() is a user-space function in the C library and cannot serve as
+               NOTE 03: sigpause() is a user-space function in the C library and cannot serve as
                cancellation points.  It is, however, a simple wrapper around sigsuspend()
                which is a true cancellation point.
-               NOTE 4: aio_suspend() is a user-space function in the C library and cannot serve as
+               NOTE 04: aio_suspend() is a user-space function in the C library and cannot serve as
                cancellation points.  It does call around sigtimedwait() which is a true cancellation
                point.
   Status:      Not really open.  This is just the way it is.
@@ -1530,7 +1530,7 @@ o Libraries (libc/, libm/)
   Description: There are many things implemented within the kernel (for example
                under sched/pthread) that probably should be migrated in the
                C library where it belongs.
-  Status:      Open
+  Status:      Ope
   Priority:    Low
 
 o File system / Generic drivers (fs/, drivers/)

fs/aio/aio_cancel.c

@@ -61,30 +61,30 @@
  *   The aio_cancel() function attempts to cancel one or more asynchronous
  *   I/O requests currently outstanding against file descriptor 'fildes'.
  *   The aiocbp argument points to the asynchronous I/O control block for
- *   a particular request to be cancelled. If aiocbp is NULL, then all
+ *   a particular request to be canceled. If aiocbp is NULL, then all
  *   outstanding cancelable asynchronous I/O requests against fildes will
- *   be cancelled.
+ *   be canceled.
  *
  *   Normal asynchronous notification will occur for asynchronous I/O
- *   operations that are successfully cancelled. If there are requests that
+ *   operations that are successfully canceled. If there are requests that
- *   cannot be cancelled, then the normal asynchronous completion process
+ *   cannot be canceled, then the normal asynchronous completion process
  *   will take place for those requests when they are completed.
  *
- *   For requested operations that are successfully cancelled, the associated
+ *   For requested operations that are successfully canceled, the associated
  *   error status will be set to ECANCELED and the return status will be -1.
- *   For requested operations that are not successfully cancelled, the aiocbp
+ *   For requested operations that are not successfully canceled, the aiocbp
  *   will not be modified by aio_cancel().
  *
  * Input Parameters:
  *   fildes - Not used in this implementation
  *   aiocbp - Points to the asynchronous I/O control block for a particular
- *            request to be cancelled.
+ *            request to be canceled.
  *
  * Returned Value:
  *    The aio_cancel() function will return the value AIO_CANCELED if the
- *    requested operation(s) were cancelled. The value AIO_NOTCANCELED will
+ *    requested operation(s) were canceled. The value AIO_NOTCANCELED will
  *    be returned if at least one of the requested operation(s) cannot be
- *    cancelled because it is in progress. In this case, the state of the
+ *    canceled because it is in progress. In this case, the state of the
  *    other operations, if any, referenced in the call to aio_cancel() is
  *    not indicated by the return value of aio_cancel(). The application
  *    may determine the state of affairs for these operations by using
@@ -133,7 +133,7 @@ int aio_cancel(int fildes, FAR struct aiocb *aiocbp)
                * possibilities:* (1) the work has already been started and
                * is no longer queued, or (2) the work has not been started
                * and is still in the work queue.  Only the second case can
-               * be cancelled.  work_cancel() will return -ENOENT in the
+               * be canceled.  work_cancel() will return -ENOENT in the
                * first case.
                */
 
@@ -177,7 +177,7 @@ int aio_cancel(int fildes, FAR struct aiocb *aiocbp)
                * possibilities:* (1) the work has already been started and
                * is no longer queued, or (2) the work has not been started
                * and is still in the work queue.  Only the second case can
-               * be cancelled.  work_cancel() will return -ENOENT in the
+               * be canceled.  work_cancel() will return -ENOENT in the
                * first case.
                */
 

fs/aio/aio_read.c

@@ -226,7 +226,7 @@ static void aio_read_worker(FAR void *arg)
  *     aiocbp->aio_nbytes is an invalid value.
  *
  *   In the case that the aio_read() successfully queues the I/O operation
- *   but the operation is subsequently cancelled or encounters an error, the
+ *   but the operation is subsequently canceled or encounters an error, the
  *   return status of the asynchronous operation is one of the values
  *   normally returned by the read() function call. In addition, the error
  *   status of the asynchronous operation is set to one of the error
@@ -235,7 +235,7 @@ static void aio_read_worker(FAR void *arg)
  *
  *   EBADF - The aiocbp->aio_fildes argument is not a valid file descriptor
  *     open for reading.
- *   ECANCELED - The requested I/O was cancelled before the I/O completed
+ *   ECANCELED - The requested I/O was canceled before the I/O completed
  *     due to an explicit aio_cancel() request.
  *   EINVAL - The file offset value implied by aiocbp->aio_offset would be
  *     invalid.

fs/aio/aio_write.c

@@ -279,7 +279,7 @@ errout:
  *     aiocbp->aio_nbytes is an invalid value.
  *
  *   In the case that the aio_write() successfully queues the I/O operation
- *   but the operation is subsequently cancelled or encounters an error, the
+ *   but the operation is subsequently canceled or encounters an error, the
  *   return status of the asynchronous operation is one of the values
  *   normally returned by the write() function call. In addition, the error
  *   status of the asynchronous operation is set to one of the error
@@ -290,7 +290,7 @@ errout:
  *     open for writing.
  *   EINVAL - The file offset value implied by aiocbp->aio_offset would be
  *     invalid.
- *   ECANCELED - The requested I/O was cancelled before the I/O completed
+ *   ECANCELED - The requested I/O was canceled before the I/O completed
  *     due to an explicit aio_cancel() request.
  *
  * The following condition may be detected synchronously or asynchronously:

fs/mount/fs_automount.c

@@ -485,7 +485,7 @@ static int automount_interrupt(FAR const struct automount_lower_s *lower,
   /* Queue work to occur after a delay.  The delays performs debouncing:
    * If the insertion/removal detection logic has "chatter", then we may
    * receive this interrupt numerous times.  Each time, the previous work
-   * will be cancelled (above) and the new work will scheduled with the
+   * will be canceled (above) and the new work will scheduled with the
    * delay.  So the final mount operation will not be performed until the
    * insertion state is stable for that delay.
    */

sched/pthread/pthread_condwait.c

@@ -107,7 +107,11 @@ int pthread_cond_wait(FAR pthread_cond_t *cond, FAR pthread_mutex_t *mutex)
       ret |= pthread_takesemaphore((FAR sem_t *)&cond->sem);
       sched_unlock();
 
-      /* Reacquire the mutex */
+      /* Reacquire the mutex.
+       *
+       * REVISIT: When cancellation points are enabled, we will almost
+       * certainly hold the mutex when the pthread is canceled.
+       */
 
       sinfo("Reacquire mutex...\n");
       ret |= pthread_takesemaphore((FAR sem_t *)&mutex->sem);

sched/pthread/pthread_mutexdestroy.c

@@ -75,7 +75,7 @@ int pthread_mutex_destroy(FAR pthread_mutex_t *mutex)
 
   sinfo("mutex=0x%p\n", mutex);
 
-  if (!mutex)
+  if (mutex == NULL)
     {
       ret = EINVAL;
     }
@@ -100,7 +100,7 @@ int pthread_mutex_destroy(FAR pthread_mutex_t *mutex)
          ret = kill(mutex->pid, 0);
          if (ret < 0)
            {
-             /* That thread associated with the PID no longer exists */
+             /* The thread associated with the PID no longer exists */
 
              mutex->pid = -1;