Address several issues from compiling examples

Compiling the code from examples "code-block:: c" along with public
includes and a bsp exposed a few issues amongst a lot of false
positives. Address some of these:

* Terminate struct declarations with ';'. Mainly for pedantic
  correctness.

* Show ptrdiff_t instead of size_t for the sbrk() prototype, matching
  the current argument type in rtems.

* Replace some occurrences of unsigned16 with uint16_t.

* Fix odd type declaration, "uint8_t char*" -> "char*".

* Use appropriate helper to get chain head instead of invalid access to
  nonexistent struct member.

* Remove several excess '\' escapes.

* Use RTEMS_SELF instead of undefined SELF.

* Use rtems_task instead of void for task functions.

* Add missing stack size parameter in task creation.

* Use rtems_interrupt_level instead of undefined rtems_interrupt.

* Correct return value format for rtems_object_id_get_api()
  rtems_object_id_get_index() (enum and uint16_t) and also fix
  corresponding print formatting.

* Correct return value documentation for rtems_object_id_get_class(),
  rtems_object_id_get_node() and rtems_object_id_get_index()
  int -> uint32_t.

* Use RTEMS_SUCCESSFUL instead of undefined RTEMS_STATUS_SUCCESSFUL and
  fix return value variable name in rate monotonic examples.

* Use RTEMS_TIMEOUT instead of undefined TIMEOUT and RTEMS_PERIOD_STATUS
  instead of undefined STATUS.

* Add missing fields to ftpd configuration.

* Correct parameter types in ftpd hook prototype,
  unsigned char * -> void *.

* Fix various code-block:: attributes, c -> makefile and c -> shell.

* Add missing parenthesis in socket buffer memory calculation example.

* Remove typedef in declaration of mq_attr since it is defiend without
  typedef in reality.

* Update siginfo_t declaration to match current reality.

* Update shell user command definition example to include mode, uid and
  gid.

1 files changed, 2 insertions, 2 deletions

diff --git a/c-user/chains.rst b/c-user/chains.rst
index c47d318..0dce1d9 100644
--- a/c-user/chains.rst
+++ b/c-user/chains.rst
@@ -149,7 +149,7 @@ to the control. Consider a user structure and chain control:
     typedef struct foo
     {
         rtems_chain_node node;
-        uint8_t char*    data;
+        char*            data;
     } foo;
     rtems_chain_control chain;
 
@@ -192,7 +192,7 @@ placed on another chain:
 
         rtems_chain_initialize_empty (out);
 
-        node = chain->first;
+        node = rtems_chain_head (chain);
         while (!rtems_chain_is_tail (chain, node))
         {
             bar = (foo*) node;