1<h2>i386_set_ldt</h2>
2<hr>
3<p>
4<strong>Function</strong> - Set per-thread segment descriptors.
5<h3>SYNOPSIS</h3>
6<pre>
7<strong>kern_return_t   i386_set_ldt</strong>
8                <strong>(thread_act_t</strong>                        <var>target_act</var>,
9                 <strong>int</strong>                             <var>first_selector</var>,
10                 <strong>descriptor_list_t</strong>                    <var>desc_list</var><strong>);</strong>
11</pre>
12<h3>PARAMETERS</h3>
13<dl>
14<p>
15<dt> <var>target_act</var> 
16<dd>
17[in thread send right]
18Thread whose segment descriptors are to be set.
19<p>
20<dt> <var>first_selector</var> 
21<dd>
22[in scalar]
23Selector value (segment register value) corresponding to the 
24first segment whose descriptor is to be set.
25<p>
26<dt> <var>desc_list</var> 
27<dd>
28[pointer to in array of <strong>descriptor_t</strong>]
29Array of segment descriptors.  The 
30following forms are permitted:
31<ul>
32<p>
33<li>
34Empty descriptor. The <strong>ACC_P</strong> flag (segment present) may or may 
35not be set.
36<p>
37<li>
38<strong>ACC_CALL_GATE</strong>--Converted into a system call gate.  The 
39<strong>ACC_P</strong> flag must be set.
40</ul>
41<p>
42All other descriptors must have both the <strong>ACC_P</strong> flag set and specify 
43user mode access (<strong>ACC_PL_U</strong>).
44<ul>
45<p>
46<li>
47<strong>ACC_DATA</strong>.
48<p>
49<li>
50<strong>ACC_DATA_W</strong>.
51<p>
52<li>
53<strong>ACC_DATA_E</strong>.
54<p>
55<li>
56<strong>ACC_DATA_EW</strong>.
57<p>
58<li>
59<strong>ACC_CODE</strong>.
60<p>
61<li>
62<strong>ACC_CODE_R</strong>.
63<p>
64<li>
65<strong>ACC_CODE_C</strong>.
66<p>
67<li>
68<strong>ACC_CODE_CR</strong>.
69<p>
70<li>
71<strong>ACC_CALL_GATE_16</strong>.
72<p>
73<li>
74<strong>ACC_CALL_GATE</strong>.
75</ul>
76</dl>
77<h3>DESCRIPTION</h3>
78<p>
79The <strong>i386_set_ldt</strong> function allows a thread to have a
80private local descriptor
81table (LDT) which allows its local segments to map various ranges
82of its address 
83space.
84<h3>RETURN VALUES</h3>
85<p>
86Only generic errors apply.
87<h3>RELATED INFORMATION</h3>
88<p>
89Functions:
90<a href="i386_get_ldt.html"><strong>i386_get_ldt<strong></a>.
91