Merged signals-merge branch into trunk with the following changes:

* Reorganized the kernel locking related to threads and teams.
* We now discriminate correctly between process and thread signals. Signal
  handlers have been moved to teams. Fixes #5679.
* Implemented real-time signal support, including signal queuing, SA_SIGINFO
  support, sigqueue(), sigwaitinfo(), sigtimedwait(), waitid(), and the addition
  of the real-time signal range. Closes #1935 and #2695.
* Gave SIGBUS a separate signal number. Fixes #6704.
* Implemented <time.h> clock and timer support, and fixed/completed alarm() and
  [set]itimer(). Closes #5682.
* Implemented support for thread cancellation. Closes #5686.
* Moved send_signal() from <signal.h> to <OS.h>. Fixes #7554.
* Lots over smaller more or less related changes.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@42116 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/os/kernel/OS.h

@@ -311,6 +311,8 @@ typedef struct {
 #define B_REAL_TIME_PRIORITY			120
 
 #define B_SYSTEM_TIMEBASE				0
+	/* time base for snooze_*(), compatible with the clockid_t constants defined
+	   in <time.h> */
 
 #define B_FIRST_REAL_TIME_PRIORITY		B_REAL_TIME_DISPLAY_PRIORITY
 
@@ -739,6 +741,11 @@ extern int32		is_computer_on(void);
 extern double		is_computer_on_fire(void);
 
 
+/* signal related functions */
+int		send_signal(thread_id threadID, unsigned int signal);
+void	set_signal_stack(void* base, size_t size);
+
+
 /* WARNING: Experimental API! */
 
 enum {