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+--
+--  $Id$
+--
+
+Overview of newlib support (newlib is from CYGNUS)
+    Each task can have its own libc state including:
+        open stdio files
+        strtok
+        multi precision arithmetic state
+        etc.
+
+    This is implemented by a reentrancy data structure for each task.
+
+    When a task is "started" (in RTEMS sense) the reentrancy structure
+    is allocated.  Its address is stored in notepad[NOTEPAD_LAST].
+
+    When task is switched to, the value of global variable _impure_ptr
+    is changed to the value of the new tasks reentrancy structure.
+
+    When a task is deleted
+        atexit() processing (for that task) happens
+        task's stdio buffers are flushed
+
+    When exit(3) is called
+        calling task's atexit processing done
+        global libc state atexit processing done
+            (this will include any atexit routines installed by drivers)
+        executive is shutdown
+            causes a context switch back to bsp land
+
+
+NOTE:
+    libc extension are installed by bsp_libc_init()
+        iff we are using clock interrupts.
+        This hack is necessary to allow the tmtests to avoid
+        timing the extensions.
+