LXR darwin-xnu/osfmk/man/exc

   1<h2>exc_server</h2>
   2<hr>
   3<p>
   4<strong>Function</strong> - Handle kernel-reported thread exception.
   5<h3>SYNOPSIS</h3>
   6<pre>
   7<strong>boolean_t       exc_server</strong>
   8                <strong>(mach_msg_header_t</strong>     <var>request_msg</var>,
   9                <strong>mach_msg_header_t</strong>      <var>reply_ms</var><strong>);</strong>
  10</pre>
  11<h3>PARAMETERS</h3>
  12<dl>
  13<p>
  14<dt> <var>in_msg</var> 
  15<dd>
  16[pointer to in structure]
  17The exception message received from the
  18kernel.
  19<p>
  20<dt> <var>out_msg</var> 
  21<dd>
  22[out structure]
  23A reply message. 
  24</dl>
  25<h3>DESCRIPTION</h3>
  26<p>
  27The <strong>exc_server</strong> function is the MIG generated server
  28handling function to
  29handle messages from the kernel relating to the occurrence of
  30an exception in a 
  31thread.  Such messages are delivered to the exception port set via
  32<strong>thread_set_exception_ports</strong> or <strong>task_set_exception_ports</strong>.  
  33When an exception occurs in a 
  34thread, the thread sends an exception message to its exception port, blocking in 
  35the kernel waiting for the receipt of a reply.  The <strong>exc_server</strong>
  36function performs 
  37all necessary argument handling for this kernel message and calls
  38<strong>catch_exception_raise</strong>, <strong>catch_exception_raise_state</strong> or
  39<strong>catch_exception_raise_state_identity</strong>, which should handle the
  40exception.  If the called routine 
  41returns <strong>KERN_SUCCESS</strong>, a reply message will be sent, allowing
  42the thread to 
  43continue from the point of the exception; otherwise, no reply message is sent 
  44and the called routine must have dealt with the exception thread directly.
  45<h3>RETURN VALUES</h3>
  46<dl>
  47<p>
  48<dt> <strong>TRUE</strong>
  49<dd>
  50The message was handled and the appropriate function was called.
  51<p>
  52<dt> <strong>FALSE</strong>
  53<dd>
  54The message did not apply to the exception mechanism and no other 
  55action was taken.
  56</dl>
  57<h3>RELATED INFORMATION</h3>
  58<p>
  59Functions:
  60<a href="catch_exception_raise.html"><strong>catch_exception_raise<strong></a>.
  61