Reorganized system call library; uses separate file per call now.

New configuration header file to include/ exclude functionality.
Extracted privileged features from struct proc and create new struct priv.
Renamed various system calls for readability.

kernel/system/do_kill.c

@@ -0,0 +1,41 @@
+/* The system call that is implemented in this file:
+ *     SYS_SIGCTL	# signal handling functionality 
+ *
+ * The parameters and types for this system call are:
+ *     SIG_REQUEST 	# request to perform			(long)
+ *     SIG_PROC  	# process to signal/ pending		(int)
+ *     SIG_CTXT_PTR 	# pointer to sigcontext structure	(pointer)	
+ *     SIG_FLAGS    	# flags for S_SIGRETURN call		(int)	
+ *     SIG_MAP		# bit map with pending signals		(long)	
+ *     SIG_NUMBER	# signal number to send to process	(int)	
+ *
+ * Supported request types are in the parameter SIG_REQUEST:
+ *     S_GETSIG		# get a pending kernel signal
+ *     S_ENDSIG		# signal has been processed 
+ *     S_SENDSIG	# deliver a POSIX-style signal 
+ *     S_SIGRETURN	# return from a POSIX-style signal 
+ *     S_KILL		# send a signal to a process 
+ */
+
+#include "../system.h"
+#include <signal.h>
+#include <sys/sigcontext.h>
+
+#if USE_KILL
+
+/*===========================================================================*
+ *			          do_kill				     *
+ *===========================================================================*/
+PUBLIC int do_kill(m_ptr)
+message *m_ptr;			/* pointer to request message */
+{
+/* Handle sys_kill(). Cause a signal to be sent to a process via PM.
+ * Note that this has nothing to do with the kill (2) system call, this
+ * is how the FS (and possibly other servers) get access to cause_sig. 
+ */
+  cause_sig(m_ptr->SIG_PROC, m_ptr->SIG_NUMBER);
+  return(OK);
+}
+
+#endif /* USE_KILL */
+