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35 .Dd September 20, 1993
41 .Nd manage i386 per-process Local Descriptor Table entries
43 .Fd #include <machine/segments.h>
44 .Fd #include <machine/sysarch.h>
46 .Fn i386_get_ldt "int start_sel" "union descriptor *descs" "int num_sels"
48 .Fn i386_set_ldt "int start_sel" "union descriptor *descs" "int num_sels"
51 will return the list of i386 descriptors that the process has in its
54 will set a list of i386 descriptors for the current process in its
56 Both routines accept a starting selector number
58 , an array of memory that
59 will contain the descriptors to be set or returned
61 , and the number of entries to set or return
66 can be either segment_descriptor or gate_descriptor and are defined in
67 .Fd <i386/segments.h> .
68 These structures are defined by the architecture
69 as disjoint bit-fields, so care must be taken in constructing them.
71 Upon successful completion,
73 returns the number of descriptors currently in the LDT.
75 returns the first selector set.
76 Otherwise, a value of -1 is returned and the global
79 is set to indicate the error.
85 .Bl -tag -width [EINVAL]
87 An inappropriate parameter was used for
92 The caller attempted to use a descriptor that would
93 circumvent protection or cause a failure.
96 i386 Microprocessor Programmer's Reference Manual, Intel
98 You can really hose your process using this.