1*0f4c859eSApple OSS Distributions<h2>task_sample</h2> 2*0f4c859eSApple OSS Distributions<hr> 3*0f4c859eSApple OSS Distributions<p> 4*0f4c859eSApple OSS Distributions<strong>Function</strong> - Sample the target task's thread program counters periodically. 5*0f4c859eSApple OSS Distributions<h3>SYNOPSIS</h3> 6*0f4c859eSApple OSS Distributions<pre> 7*0f4c859eSApple OSS Distributions<strong>kern_return_t task_sample</strong> 8*0f4c859eSApple OSS Distributions <strong>(task_t</strong> <var>sample_task</var>, 9*0f4c859eSApple OSS Distributions <strong>mach_port_make_send_t</strong> <var>reply_port</var><strong>);</strong> 10*0f4c859eSApple OSS Distributions</pre> 11*0f4c859eSApple OSS Distributions<h3>PARAMETERS</h3> 12*0f4c859eSApple OSS Distributions<dl> 13*0f4c859eSApple OSS Distributions<p> 14*0f4c859eSApple OSS Distributions<dt> <var>sample_task</var> 15*0f4c859eSApple OSS Distributions<dd> 16*0f4c859eSApple OSS Distributions[in task send right] 17*0f4c859eSApple OSS DistributionsPort for the task whose threads' PC are to be 18*0f4c859eSApple OSS Distributionssampled. 19*0f4c859eSApple OSS Distributions<p> 20*0f4c859eSApple OSS Distributions<dt> <var>reply_port</var> 21*0f4c859eSApple OSS Distributions<dd> 22*0f4c859eSApple OSS Distributions[in sample receive (to be converted to send) right] 23*0f4c859eSApple OSS DistributionsPort to which PC sample buffers are sent. A value of <strong>MACH_PORT_NULL</strong> 24*0f4c859eSApple OSS Distributionsstops PC sampling for the task. 25*0f4c859eSApple OSS Distributions</dl> 26*0f4c859eSApple OSS Distributions<h3>DESCRIPTION</h3> 27*0f4c859eSApple OSS Distributions<p> 28*0f4c859eSApple OSS DistributionsThe <strong>task_sample</strong> function causes the program counter (PC) of the 29*0f4c859eSApple OSS Distributionsspecified <var>sample_task</var> (actually, all of the threads within 30*0f4c859eSApple OSS Distributions<var>sample_task</var>) to be sampled periodically (whenever one of the threads 31*0f4c859eSApple OSS Distributionshappens to be running at the time of the kernel's "hardclock" interrupt). 32*0f4c859eSApple OSS DistributionsThe set of PC sample values obtained are saved in buffers which are sent to 33*0f4c859eSApple OSS Distributionsthe specified <var>reply_port</var> in <strong>receive_samples</strong> messages. 34*0f4c859eSApple OSS Distributions<h3>RETURN VALUES</h3> 35*0f4c859eSApple OSS Distributions<p> 36*0f4c859eSApple OSS DistributionsOnly generic errors apply. 37*0f4c859eSApple OSS Distributions<h3>RELATED INFORMATION</h3> 38*0f4c859eSApple OSS Distributions<p> 39*0f4c859eSApple OSS DistributionsFunctions: 40*0f4c859eSApple OSS Distributions<a href="thread_sample.html"><strong>thread_sample</strong></a>, 41*0f4c859eSApple OSS Distributions<a href="receive_samples.html"><strong>receive_samples</strong></a>. 42