1.\"	$NetBSD: dwarf_formexprloc.3,v 1.2 2014/03/09 16:58:03 christos Exp $
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3.\" Copyright (c) 2010 Joseph Koshy
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27.\" Id: dwarf_formexprloc.3 2073 2011-10-27 03:30:47Z jkoshy
28.\"
29.Dd July 25, 2010
30.Os
31.Dt DWARF_FORMEXPRLOC 3
32.Sh NAME
33.Nm dwarf_formexprloc
34.Nd return information about a location expression
35.Sh LIBRARY
36.Lb libdwarf
37.Sh SYNOPSIS
38.In libdwarf.h
39.Ft int
40.Fo dwarf_formexprloc
41.Fa "Dwarf_Attribute attr"
42.Fa "Dwarf_Unsigned *retlen"
43.Fa "Dwarf_Ptr *retexpr"
44.Fa "Dwarf_Error *err"
45.Fc
46.Sh DESCRIPTION
47Function
48.Fn dwarf_formexprloc
49allows an application to retrieve the length and the bytes of a
50DWARF location expression.
51.Pp
52Argument
53.Ar attr
54should reference a DWARF attribute of the form
55.Dv DW_FORM_exprloc .
56Argument
57.Ar retlen
58should point to a location that will be set to the length of the
59location expression.
60Argument
61.Ar retexpr
62should point to a location that will be set to a pointer to the
63content of the location expression itself.
64.Pp
65If argument
66.Ar err
67is not NULL, it will be used to return an error descriptor in case
68of an error.
69.Ss Memory Management
70The application should not attempt to free the memory
71area referenced by the pointer returned in argument
72.Ar retexpr .
73.Sh RETURN VALUES
74Function
75.Fn dwarf_formexprloc
76returns
77.Dv DW_DLV_OK
78on success.
79In case of an error, it returns
80.Dv DW_DLV_ERROR
81and sets argument
82.Ar err .
83.Sh ERRORS
84Function
85.Fn dwarf_formexprloc
86may fail with the following errors:
87.Bl -tag -width ".Bq Er DW_DLE_ATTR_FORM_BAD"
88.It Bq Er DW_DLE_ARGUMENT
89One of arguments
90.Ar attr ,
91.Ar retlen
92or
93.Ar retexpr
94was NULL.
95.It Bq Er DW_DLE_ATTR_FORM_BAD
96The attribute referenced by argument
97.Ar attr
98was not of form
99.Dv DW_FORM_exprloc .
100.El
101.Sh SEE ALSO
102.Xr dwarf 3 ,
103.Xr dwarf_attr 3 ,
104.Xr dwarf_formblock 3 ,
105.Xr dwarf_formflag 3 ,
106.Xr dwarf_formref 3 ,
107.Xr dwarf_formsdata 3 ,
108.Xr dwarf_formsig8 3 ,
109.Xr dwarf_formstring 3 ,
110.Xr dwarf_formudata 3 ,
111.Xr dwarf_hasattr 3
112