1*c54f35caSApple OSS Distributions<h2>thread_suspend</h2> 2*c54f35caSApple OSS Distributions<hr> 3*c54f35caSApple OSS Distributions<p> 4*c54f35caSApple OSS Distributions<strong>Function</strong> - Suspend a thread. 5*c54f35caSApple OSS Distributions<h3>SYNOPSIS</h3> 6*c54f35caSApple OSS Distributions<pre> 7*c54f35caSApple OSS Distributions<strong>kern_return_t thread_suspend</strong> 8*c54f35caSApple OSS Distributions <strong>(thread_act_t</strong> <var>target_thread</var><strong>);</strong> 9*c54f35caSApple OSS Distributions</pre> 10*c54f35caSApple OSS Distributions<h3>PARAMETERS</h3> 11*c54f35caSApple OSS Distributions<dl> 12*c54f35caSApple OSS Distributions<p> 13*c54f35caSApple OSS Distributions<dt> <var>target_thread</var> 14*c54f35caSApple OSS Distributions<dd> 15*c54f35caSApple OSS Distributions[in thread send right] 16*c54f35caSApple OSS DistributionsThe thread to be suspended. 17*c54f35caSApple OSS Distributions</dl> 18*c54f35caSApple OSS Distributions<h3>DESCRIPTION</h3> 19*c54f35caSApple OSS Distributions<p> 20*c54f35caSApple OSS DistributionsThe <strong>thread_suspend</strong> function increments the suspend 21*c54f35caSApple OSS Distributionscount for <var>target_thread</var> 22*c54f35caSApple OSS Distributionsand prevents the thread from executing any more user-level instructions. 23*c54f35caSApple OSS Distributions<p> 24*c54f35caSApple OSS DistributionsIn this context, a user-level instruction can be either a machine instruction 25*c54f35caSApple OSS Distributionsexecuted in user mode or a system trap instruction, including 26*c54f35caSApple OSS Distributionsa page fault. If a 27*c54f35caSApple OSS Distributionsthread is currently executing within a system trap, the kernel 28*c54f35caSApple OSS Distributionscode may continue 29*c54f35caSApple OSS Distributionsto execute until it reaches the system return code or it may 30*c54f35caSApple OSS Distributionssuspend within the 31*c54f35caSApple OSS Distributionskernel code. In either case, the system trap returns when the thread resumes. 32*c54f35caSApple OSS Distributions<p> 33*c54f35caSApple OSS DistributionsTo resume a suspended thread, use <strong>thread_resume</strong>. If 34*c54f35caSApple OSS Distributionsthe suspend count is 35*c54f35caSApple OSS Distributionsgreater than one, <strong>thread_resume</strong> must be repeated that 36*c54f35caSApple OSS Distributionsnumber of times. 37*c54f35caSApple OSS Distributions<h3>CAUTIONS</h3> 38*c54f35caSApple OSS Distributions<p> 39*c54f35caSApple OSS DistributionsUnpredictable results may occur if a program suspends a thread and alters its 40*c54f35caSApple OSS Distributionsuser state so that its direction is changed upon resuming. Note that the 41*c54f35caSApple OSS Distributions<strong>thread_abort</strong> function allows a system call to be aborted 42*c54f35caSApple OSS Distributionsonly if it is progressing in a 43*c54f35caSApple OSS Distributionspredictable way. 44*c54f35caSApple OSS Distributions<h3>RETURN VALUES</h3> 45*c54f35caSApple OSS Distributions<p> 46*c54f35caSApple OSS DistributionsOnly generic errors apply. 47*c54f35caSApple OSS Distributions<h3>RELATED INFORMATION</h3> 48*c54f35caSApple OSS Distributions<p> 49*c54f35caSApple OSS DistributionsFunctions: 50*c54f35caSApple OSS Distributions<a href="task_resume.html"><strong>task_resume</strong></a>, 51*c54f35caSApple OSS Distributions<a href="task_suspend.html"><strong>task_suspend</strong></a>, 52*c54f35caSApple OSS Distributions<a href="thread_abort.html"><strong>thread_abort</strong></a>, 53*c54f35caSApple OSS Distributions<a href="thread_get_state.html"><strong>thread_get_state</strong></a>, 54*c54f35caSApple OSS Distributions<a href="thread_info.html"><strong>thread_info</strong></a>, 55*c54f35caSApple OSS Distributions<a href="thread_resume.html"><strong>thread_resume</strong></a>, 56*c54f35caSApple OSS Distributions<a href="thread_set_state.html"><strong>thread_set_state</strong></a>, 57*c54f35caSApple OSS Distributions<a href="thread_terminate.html"><strong>thread_terminate</strong></a>. 58