* src/common/kapi.cxx: * include/kapi.h: Added function cyg_thread_get_next(), cyg_thread_find() and cyg_thread_get_info() to allow the current set of threads to be enumerated, and per-thread information to be retrieved safely. * doc/kernel.sgml: Documented new KAPI calls. * src/common/thread.cxx: Zero unique_id in thread destructor so that a stale thread pointer can be checked for validity. * include/instrmnt.h: Added cyg_instrument_state() to report the current state of an instrumentation flag. Moved ifdef for CYGDBG_KERNEL_INSTRUMENT_MSGS out of within FLAGS ifdef. We can have messages without flags. * src/instrmnt/meminst.cxx: Added cyg_instrument_state() to report the current state of an instrumentation flag. Modified cyg_instrument_msg() in line with header and table changes. * host/instr/dump_instr.c: * host/instr/instrument.sh: * include/instrument_desc.h: Added a final NULL element to the generated table in instrument_desc.h to mark its end. Otherwise code that does not have access to the table definition cannot find its end. Also added ifdefs to allow instrument_desc.h to be used to acquire the structure definition and table pointer.

--- a/packages/kernel/current/src/common/thread.cxx
+++ b/packages/kernel/current/src/common/thread.cxx
@@ -295,6 +295,9 @@ Cyg_Thread::~Cyg_Thread()
     remove_from_list();
 #endif 
     
+    // Zero the unique_id to render this thread inconsistent.
+    unique_id = 0;
+    
     CYG_REPORT_RETURN();
 }