1*1b191cb5SApple OSS Distributions<h2>thread_suspend</h2> 2*1b191cb5SApple OSS Distributions<hr> 3*1b191cb5SApple OSS Distributions<p> 4*1b191cb5SApple OSS Distributions<strong>Function</strong> - Suspend a thread. 5*1b191cb5SApple OSS Distributions<h3>SYNOPSIS</h3> 6*1b191cb5SApple OSS Distributions<pre> 7*1b191cb5SApple OSS Distributions<strong>kern_return_t thread_suspend</strong> 8*1b191cb5SApple OSS Distributions <strong>(thread_act_t</strong> <var>target_thread</var><strong>);</strong> 9*1b191cb5SApple OSS Distributions</pre> 10*1b191cb5SApple OSS Distributions<h3>PARAMETERS</h3> 11*1b191cb5SApple OSS Distributions<dl> 12*1b191cb5SApple OSS Distributions<p> 13*1b191cb5SApple OSS Distributions<dt> <var>target_thread</var> 14*1b191cb5SApple OSS Distributions<dd> 15*1b191cb5SApple OSS Distributions[in thread send right] 16*1b191cb5SApple OSS DistributionsThe thread to be suspended. 17*1b191cb5SApple OSS Distributions</dl> 18*1b191cb5SApple OSS Distributions<h3>DESCRIPTION</h3> 19*1b191cb5SApple OSS Distributions<p> 20*1b191cb5SApple OSS DistributionsThe <strong>thread_suspend</strong> function increments the suspend 21*1b191cb5SApple OSS Distributionscount for <var>target_thread</var> 22*1b191cb5SApple OSS Distributionsand prevents the thread from executing any more user-level instructions. 23*1b191cb5SApple OSS Distributions<p> 24*1b191cb5SApple OSS DistributionsIn this context, a user-level instruction can be either a machine instruction 25*1b191cb5SApple OSS Distributionsexecuted in user mode or a system trap instruction, including 26*1b191cb5SApple OSS Distributionsa page fault. If a 27*1b191cb5SApple OSS Distributionsthread is currently executing within a system trap, the kernel 28*1b191cb5SApple OSS Distributionscode may continue 29*1b191cb5SApple OSS Distributionsto execute until it reaches the system return code or it may 30*1b191cb5SApple OSS Distributionssuspend within the 31*1b191cb5SApple OSS Distributionskernel code. In either case, the system trap returns when the thread resumes. 32*1b191cb5SApple OSS Distributions<p> 33*1b191cb5SApple OSS DistributionsTo resume a suspended thread, use <strong>thread_resume</strong>. If 34*1b191cb5SApple OSS Distributionsthe suspend count is 35*1b191cb5SApple OSS Distributionsgreater than one, <strong>thread_resume</strong> must be repeated that 36*1b191cb5SApple OSS Distributionsnumber of times. 37*1b191cb5SApple OSS Distributions<h3>CAUTIONS</h3> 38*1b191cb5SApple OSS Distributions<p> 39*1b191cb5SApple OSS DistributionsUnpredictable results may occur if a program suspends a thread and alters its 40*1b191cb5SApple OSS Distributionsuser state so that its direction is changed upon resuming. Note that the 41*1b191cb5SApple OSS Distributions<strong>thread_abort</strong> function allows a system call to be aborted 42*1b191cb5SApple OSS Distributionsonly if it is progressing in a 43*1b191cb5SApple OSS Distributionspredictable way. 44*1b191cb5SApple OSS Distributions<h3>RETURN VALUES</h3> 45*1b191cb5SApple OSS Distributions<p> 46*1b191cb5SApple OSS DistributionsOnly generic errors apply. 47*1b191cb5SApple OSS Distributions<h3>RELATED INFORMATION</h3> 48*1b191cb5SApple OSS Distributions<p> 49*1b191cb5SApple OSS DistributionsFunctions: 50*1b191cb5SApple OSS Distributions<a href="task_resume.html"><strong>task_resume</strong></a>, 51*1b191cb5SApple OSS Distributions<a href="task_suspend.html"><strong>task_suspend</strong></a>, 52*1b191cb5SApple OSS Distributions<a href="thread_abort.html"><strong>thread_abort</strong></a>, 53*1b191cb5SApple OSS Distributions<a href="thread_get_state.html"><strong>thread_get_state</strong></a>, 54*1b191cb5SApple OSS Distributions<a href="thread_info.html"><strong>thread_info</strong></a>, 55*1b191cb5SApple OSS Distributions<a href="thread_resume.html"><strong>thread_resume</strong></a>, 56*1b191cb5SApple OSS Distributions<a href="thread_set_state.html"><strong>thread_set_state</strong></a>, 57*1b191cb5SApple OSS Distributions<a href="thread_terminate.html"><strong>thread_terminate</strong></a>. 58