[apple/xnu.git] / osfmk / man / ledger_create.html

<h2>ledger_create</h2>\r<hr>\r<p>\r<strong>Function</strong> - Create a subordinate ledger.\r<h3>SYNOPSIS</h3>\r<pre>\r<strong>kern_return_t   ledger_create</strong>\r                <strong>(ledger_port_t</strong>                    <var>parent_ledger</var>,\r                 <strong>ledger_port_t</strong>                    <var>ledger_ledger</var>,\r                 <strong>ledger_port_t</strong>                     <var>child_ledger</var>,\r                 <strong>ledger_item_t</strong>                         <var>transfer</var><strong>);</strong>\r</pre>\r<h3>PARAMETERS</h3>\r<dl>\r<p>\r<dt> <var>parent_ledger</var> \r<dd>\r[in ledger send right]\rThe parent ledger.\r<p>\r<dt> <var>ledger_ledger</var> \r<dd>\r[in ledger send right]\rThe wired kernel memory ledger providing the \rspace from which the ledger itself is drawn.\r<p>\r<dt> <var>child_ledger</var> \r<dd>\r[out ledger send right]\rThe new child ledger, of the same resource type \ras the parent ledger.\r<p>\r<dt> <var>transfer</var> \r<dd>\r[in scalar]\rThe resource amount to transfer to the new ledger.\r</dl>\r<h3>DESCRIPTION</h3>\r<p>\rThe <strong>ledger_create</strong> function creates a subordinate ledger.\rResource limits can be \rtransferred from the parent ledger.  The child ledger itself\ris accounted against \rthe <var>ledger_ledger</var>.  A new ledger inherits the remote service port.\r<h3>NOTES</h3>\r<p>\rThis interface is not implemented in OSF/1 R1.3.\r<p>\rA ledger limit of <strong>LEDGER_ITEM_INFINITE</strong> allows any amount (even\rinfinity) to be withdrawn.  The root ledger has such a limit.\r<h3>RETURN VALUES</h3>\r<dl>\r<p>\r<dt> <strong>KERN_RESOURCE_SHORTAGE</strong>\r<dd>\rTransferring the resources would cause the parent ledger to exceed its \rlimits.\r<p>\r<dt> <strong>KERN_INVALID_LEDGER</strong>\r<dd>\r<var>ledger_ledger</var> is not a wired kernel memory ledger.\r</dl>\r<h3>RELATED INFORMATION</h3>\r<p>\rFunctions:\r<a href="ledger_transfer.html"><strong>ledger_transfer</strong></a>,\r<a href="ledger_terminate.html"><strong>ledger_terminate</strong></a>,\r<a href="ledger_read.html"><strong>ledger_read</strong></a>,\r<a href="ledger_set_remote.html"><strong>ledger_set_remote</strong></a>.\r