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<h2>i386_set_ldt</h2>\r<hr>\r<p>\r<strong>Function</strong> - Set per-thread segment descriptors.\r<h3>SYNOPSIS</h3>\r<pre>\r<strong>kern_return_t   i386_set_ldt</strong>\r                <strong>(thread_act_t</strong>                        <var>target_act</var>,\r                 <strong>int</strong>                             <var>first_selector</var>,\r                 <strong>descriptor_list_t</strong>                    <var>desc_list</var><strong>);</strong>\r</pre>\r<h3>PARAMETERS</h3>\r<dl>\r<p>\r<dt> <var>target_act</var> \r<dd>\r[in thread send right]\rThread whose segment descriptors are to be set.\r<p>\r<dt> <var>first_selector</var> \r<dd>\r[in scalar]\rSelector value (segment register value) corresponding to the \rfirst segment whose descriptor is to be set.\r<p>\r<dt> <var>desc_list</var> \r<dd>\r[pointer to in array of <strong>descriptor_t</strong>]\rArray of segment descriptors.  The \rfollowing forms are permitted:\r<ul>\r<p>\r<li>\rEmpty descriptor. The <strong>ACC_P</strong> flag (segment present) may or may \rnot be set.\r<p>\r<li>\r<strong>ACC_CALL_GATE</strong>--Converted into a system call gate.  The \r<strong>ACC_P</strong> flag must be set.\r</ul>\r<p>\rAll other descriptors must have both the <strong>ACC_P</strong> flag set and specify \ruser mode access (<strong>ACC_PL_U</strong>).\r<ul>\r<p>\r<li>\r<strong>ACC_DATA</strong>.\r<p>\r<li>\r<strong>ACC_DATA_W</strong>.\r<p>\r<li>\r<strong>ACC_DATA_E</strong>.\r<p>\r<li>\r<strong>ACC_DATA_EW</strong>.\r<p>\r<li>\r<strong>ACC_CODE</strong>.\r<p>\r<li>\r<strong>ACC_CODE_R</strong>.\r<p>\r<li>\r<strong>ACC_CODE_C</strong>.\r<p>\r<li>\r<strong>ACC_CODE_CR</strong>.\r<p>\r<li>\r<strong>ACC_CALL_GATE_16</strong>.\r<p>\r<li>\r<strong>ACC_CALL_GATE</strong>.\r</ul>\r</dl>\r<h3>DESCRIPTION</h3>\r<p>\rThe <strong>i386_set_ldt</strong> function allows a thread to have a\rprivate local descriptor\rtable (LDT) which allows its local segments to map various ranges\rof its address \rspace.\r<h3>RETURN VALUES</h3>\r<p>\rOnly generic errors apply.\r<h3>RELATED INFORMATION</h3>\r<p>\rFunctions:\r<a href="i386_get_ldt.html"><strong>i386_get_ldt<strong></a>.\r