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<h2>mach_port_allocate</h2>
<hr>
<p>
<strong>Function</strong> - Create caller-specified type of port right.
<h3>SYNOPSIS</h3>
<pre>
<strong>kern_return_t   mach_port_allocate</strong>
                <strong>(ipc_space_t</strong>                               <var>task</var>,
                 <strong>mach_port_right_t</strong>                        <var>right</var>,
                 <strong>mach_port_name_t</strong>                         <var>*name</var><strong>);</strong>
</pre>
<h3>PARAMETERS</h3>
<dl>
<p>
<dt> <var>task</var> 
<dd>
[in task send right]
The task acquiring the port right.
<p>
<dt> <var>right</var> 
<dd>
[in scalar]
The kind of entity to be created.  This is one of the following:
<dl>
<p>
<dt> <strong>MACH_PORT_RIGHT_RECEIVE</strong>
<dd>
<strong>mach_port_allocate</strong> creates a port.  The new port is not a 
member of any port set.  It doesn't have any extant send or 
send-once rights.  Its make-send count is zero, its sequence 
number is zero, its queue limit is <strong>MACH_PORT_QLIMIT_DEFAULT</strong>, and 
it has no queued messages.  <var>name</var> denotes the 
receive right for the new port.
<var>task</var> does not hold send rights for the new port, only the
receive right.  <strong>mach_port_insert_right</strong> and
<strong>mach_port_extract_right</strong> can be used to convert the receive right into a 
combined send/receive right.
<p>
<dt> <strong>MACH_PORT_RIGHT_PORT_SET</strong>
<dd>
<strong>mach_port_allocate</strong> creates a port set.  The new port set has 
no members.
<p>
<dt> <strong>MACH_PORT_RIGHT_DEAD_NAME</strong>
<dd>
<strong>mach_port_allocate</strong> creates a dead name.  The new dead 
name has one user reference.
</dl>
<p>
<dt> <var>name</var> 
<dd>
[out scalar]
The task's name for the port right.  This can be any name 
that wasn't in use.
</dl>
<h3>DESCRIPTION</h3>
<p>
The <strong>mach_port_allocate</strong> function creates a new right
in the specified task.  The new right's name is returned in name.
<p>
Ports that are allocated via this call do not support the full set of
Mach port semantics; in particular, the kernel will not provide no-more-senders
notification service requests on such ports.  Any attempt to request  no-more-senders
notification service
will generate an error.  Use the <strong>mach_port_allocate_full</strong>
interface to allocate ports that support the full set of Mach port semantics.
<h3>NOTES</h3>
<p>
This interface is machine word length specific because of the port name
parameter.
<h3>RETURN VALUES</h3>
<dl>
<p>
<dt> <strong>KERN_NO_SPACE</strong>
<dd>
There was no room in task's IPC name space for another right.
</dl>
<h3>RELATED INFORMATION</h3>
<p>
Functions:
<a href="mach_port_allocate_name.html"><strong>mach_port_allocate_name</strong></a>,
<a href="mach_port_deallocate.html"><strong>mach_port_deallocate</strong></a>,
<a href="mach_port_insert_right.html"><strong>mach_port_insert_right</strong></a>,
<a href="mach_port_extract_right.html"><strong>mach_port_extract_right</strong></a>.