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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]

17 The exception message received from the

18 kernel.

19 <p>

20 <dt> <var>out_msg</var>

21 <dd>

22 [out structure]

23 A reply message.

24 </dl>

25 <h3>DESCRIPTION</h3>

26 <p>

27 The <strong>exc_server</strong> function is the MIG generated server

28 handling function to

29 handle messages from the kernel relating to the occurrence of

30 an exception in a

31 thread. Such messages are delivered to the exception port set via

32 <strong>thread_set_exception_ports</strong> or <strong>task_set_exception_ports</strong>.

33 When an exception occurs in a

34 thread, the thread sends an exception message to its exception port, blocking in

35 the kernel waiting for the receipt of a reply. The <strong>exc_server</strong>

36 function performs

37 all 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

40 exception. If the called routine

41 returns <strong>KERN_SUCCESS</strong>, a reply message will be sent, allowing

42 the thread to

43 continue from the point of the exception; otherwise, no reply message is sent

44 and 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>

50 The message was handled and the appropriate function was called.

51 <p>

52 <dt> <strong>FALSE</strong>

53 <dd>

54 The message did not apply to the exception mechanism and no other

55 action was taken.

56 </dl>

57 <h3>RELATED INFORMATION</h3>

58 <p>

59 Functions:

 <a href="catch_exception_raise.html"><strong>catch_exception_raise<strong></a>.