1*c54f35caSApple OSS Distributions<h2>thread_activation_create</h2> 2*c54f35caSApple OSS Distributions<hr> 3*c54f35caSApple OSS Distributions<p> 4*c54f35caSApple OSS Distributions<strong>Function</strong> - Create a thread activation. 5*c54f35caSApple OSS Distributions<h3>SYNOPSIS</h3> 6*c54f35caSApple OSS Distributions<pre> 7*c54f35caSApple OSS Distributions<strong>kern_return_t thread_activation_create</strong> 8*c54f35caSApple OSS Distributions <strong>(task_t</strong> <var>task</var>, 9*c54f35caSApple OSS Distributions <strong>mach_port_name_t</strong> <var>RPC_port</var>, 10*c54f35caSApple OSS Distributions <strong>vm_offset_t</strong> <var>user_stack</var>, 11*c54f35caSApple OSS Distributions <strong>vm_size_t</strong> <var>stack_size</var>, 12*c54f35caSApple OSS Distributions <strong>thread_act_t</strong> <var>thread_act_t</var><strong>);</strong> 13*c54f35caSApple OSS Distributions</pre> 14*c54f35caSApple OSS Distributions<h3>PARAMETERS</h3> 15*c54f35caSApple OSS Distributions<dl> 16*c54f35caSApple OSS Distributions<p> 17*c54f35caSApple OSS Distributions<dt> <var>task</var> 18*c54f35caSApple OSS Distributions<dd> 19*c54f35caSApple OSS Distributions[in task send right] The port for the task that is to contain the new 20*c54f35caSApple OSS Distributionsthread activation. 21*c54f35caSApple OSS Distributions<p> 22*c54f35caSApple OSS Distributions<dt> <var>RPC_port</var> 23*c54f35caSApple OSS Distributions<dd> 24*c54f35caSApple OSS Distributions[in receive right] A receive right held by the task, or a port set in the 25*c54f35caSApple OSS Distributionstask. 26*c54f35caSApple OSS Distributions<p> 27*c54f35caSApple OSS Distributions<dt> <var>user_stack</var> 28*c54f35caSApple OSS Distributions<dd> 29*c54f35caSApple OSS Distributions[in scalar] The virtual address in the task to be used as the starting ad- 30*c54f35caSApple OSS Distributionsdress of the user-level stack. 31*c54f35caSApple OSS Distributions<p> 32*c54f35caSApple OSS Distributions<dt> <var>new_act</var> 33*c54f35caSApple OSS Distributions<dd> 34*c54f35caSApple OSS Distributions[out thread send right] The kernel-assigned name for the new thread ac- 35*c54f35caSApple OSS Distributionstivation. 36*c54f35caSApple OSS Distributions</dl> 37*c54f35caSApple OSS Distributions<h3>DESCRIPTION</h3> 38*c54f35caSApple OSS Distributions<p> 39*c54f35caSApple OSS DistributionsThe thread_activation_create function creates a thread activation, or 40*c54f35caSApple OSS Distributions"empty thread", into which a client thread shuttle can migrate during 41*c54f35caSApple OSS DistributionsRPC. The RPC_port must name ei- ther a receive right held by the 42*c54f35caSApple OSS Distributionstask, or a port set in the task. The new thread activation will be 43*c54f35caSApple OSS Distributionsadded to a pool of activations attached to this port (or port set). 44*c54f35caSApple OSS DistributionsIncoming RPC's targeted at the port (or one of the ports in the set) 45*c54f35caSApple OSS Distributionscan use any of the activations in the pool. That is, the client 46*c54f35caSApple OSS Distributionsthread shuttle will migrate into the specified server task, take one 47*c54f35caSApple OSS Distributionsof the thread activations out of the pool, and join up with it for the 48*c54f35caSApple OSS Distributionsduration of the RPC. The shuttle will migrate back to the original 49*c54f35caSApple OSS Distributionsclient activation at the end of the RPC. If no thread activations are 50*c54f35caSApple OSS Distributionsin the pool, RPC will be blocked until one is created in the pool, or 51*c54f35caSApple OSS Distributionsan existing one finishes its RPC and returns to the pool. 52*c54f35caSApple OSS DistributionsThe new thread activation will begin each RPC using the stack pointer 53*c54f35caSApple OSS Distributionsspecified by user_stack. The kernel neither knows nor cares how big 54*c54f35caSApple OSS Distributionsthe specified stack is. 55*c54f35caSApple OSS DistributionsWhen a short-circuited RPC (or mach_rpc) is invoked on a port created 56*c54f35caSApple OSS Distributionswith mach_port_allocate_subsystem, the RPC will begin execution in the 57*c54f35caSApple OSS Distributionssubsystem server at the work function address specified by the port 58*c54f35caSApple OSS Distributionsand routine number and looked up in the associated subsystem data. 59*c54f35caSApple OSS Distributions<h3>NOTES</h3> 60*c54f35caSApple OSS Distributions<p> 61*c54f35caSApple OSS DistributionsThe following calls targeted at a thread_act port may _not_ be called 62*c54f35caSApple OSS Distributionson an empty thread_act (and will return KERN_INVALID_ARGUMENT if 63*c54f35caSApple OSS Distributionsthey are called with one): 64*c54f35caSApple OSS Distributionsthread_abort 65*c54f35caSApple OSS Distributionsthread_abort_safely 66*c54f35caSApple OSS Distributionsthread_depress_abort 67*c54f35caSApple OSS Distributionsthread_info 68*c54f35caSApple OSS Distributionsthread_wire 69*c54f35caSApple OSS DistributionsIn addition, if thread_switch is called with an empty thread_act as 70*c54f35caSApple OSS Distributionsits first argument, the argument will be ignored (i.e., the function 71*c54f35caSApple OSS Distributionswill behave as if a zero-valued argument had been given). 72*c54f35caSApple OSS Distributions<h3>RETURN VALUES</h3> 73*c54f35caSApple OSS Distributions<p> 74*c54f35caSApple OSS DistributionsOnly generic errors apply. 75*c54f35caSApple OSS Distributions<h3>RELATED INFORMATION</h3> 76*c54f35caSApple OSS Distributions<p> 77*c54f35caSApple OSS DistributionsFunctions: 78*c54f35caSApple OSS Distributions<a href="task_create.html"><strong>task_create</strong></a>, 79*c54f35caSApple OSS Distributions<a href="MP_allocate_subsystem.html"><strong>mach_port_allocate_subsystem</strong></a>, 80