osfmk/man/mach_port_set_seqno.html

   1 <h2>mach_port_set_seqno</h2>
<hr>
<p>
<strong>Function</strong> - Change the current value of the target port's sequence number.
<h3>SYNOPSIS</h3>
<pre>
<strong>kern_return_t   mach_port_set_seqno</strong>
                <strong>(ipc_space_t</strong>                               <var>task</var>,
                 <strong>mach_port_name_t</strong>                          <var>name</var>,
                 <strong>mach_port_seqno_t</strong>                        <var>seqno</var><strong>);</strong>
</pre>
<h3>PARAMETERS</h3>
<dl>
<p>
<dt> <var>task</var> 
<dd>
[in task send right]
The task owning the receive right.
<p>
<dt> <var>name</var> 
<dd>
[in scalar]
<var>task</var>'s name for the receive right.
<p>
<dt> <var>seqno</var> 
<dd>
[in scalar]
The sequence number that the next message received from 
the port will have.
</dl>
<h3>DESCRIPTION</h3>
<p>
The <strong>mach_port_set_seqno</strong> function changes the sequence
number of <var>task</var>'s
receive right named <var>name</var>.
<p>
(Each port is associated with a sequence number attribute that can be
used to track the order in which messages sent to the port are received.
A port's sequence number is initially set to zero and is incremented each
time a message is received from the port.  A port's sequence number is
automatically reset to zero each time the port's receive right migrates.)
<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_INVALID_NAME</strong>
<dd>
<var>name</var> did not denote a right.
<p>
<dt> <strong>KERN_INVALID_RIGHT</strong>
<dd>
<var>name</var> denoted a right, but not a receive right.
</dl>
<h3>RELATED INFORMATION</h3>
<p>
Functions:
<a href="mach_port_get_attributes.html"><strong>mach_port_get_attributes</strong></a>.