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