xref: /freebsd/contrib/elftoolchain/libdwarf/dwarf_formblock.3 (revision b9f654b163bce26de79705e77b872427c9f2afa1)
1.\" Copyright (c) 2010 Joseph Koshy
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25.\" $Id: dwarf_formblock.3 3640 2018-10-14 14:09:13Z jkoshy $
26.\"
27.Dd July 23, 2010
28.Dt DWARF_FORMBLOCK 3
29.Os
30.Sh NAME
31.Nm dwarf_formblock
32.Nd return the value of a BLOCK attribute
33.Sh LIBRARY
34.Lb libdwarf
35.Sh SYNOPSIS
36.In libdwarf.h
37.Ft int
38.Fo dwarf_formblock
39.Fa "Dwarf_Attribute attr"
40.Fa "Dwarf_Block **ret"
41.Fa "Dwarf_Error *err"
42.Fc
43.Sh DESCRIPTION
44Function
45.Fn dwarf_formblock
46sets the location pointed to by argument
47.Ar ret
48to a pointer to a
49.Vt Dwarf_Block
50structure containing the value of the attribute referenced
51by argument
52.Ar attr .
53The form of argument
54.Ar attr
55must be one of
56.Dv DW_FORM_block ,
57.Dv DW_FORM_block1 ,
58.Dv DW_FORM_block2
59or
60.Dv DW_FORM_block4 .
61.Pp
62If argument
63.Ar err
64is not NULL, it will be used to return an error descriptor in case
65of an error.
66.Ss Memory Management
67The memory area referenced by the returned pointer is managed by
68the DWARF(3) library.
69The application should not attempt to free this memory
70area.
71Portable code may indicate that the memory area is to be freed by
72using
73.Xr dwarf_dealloc 3 .
74.Sh RETURN VALUES
75Function
76.Fn dwarf_formblock
77returns
78.Dv DW_DLV_OK
79on success.
80In case of an error, it returns
81.Dv DW_DLV_ERROR
82and sets argument
83.Ar err .
84.Sh ERRORS
85Function
86.Fn dwarf_formblock
87may fail with the following errors:
88.Bl -tag -width ".Bq Er DW_DLE_ATTR_FORM_BAD"
89.It Bq Er DW_DLE_ARGUMENT
90Either of arguments
91.Ar attr
92or
93.Ar ret
94was NULL.
95.It Bq Er DW_DLE_ATTR_FORM_BAD
96The attribute referenced by argument
97.Ar attr
98was not of a permitted kind.
99.El
100.Sh SEE ALSO
101.Xr dwarf 3 ,
102.Xr dwarf_attr 3 ,
103.Xr dwarf_formflag 3 ,
104.Xr dwarf_formref 3 ,
105.Xr dwarf_formsdata 3 ,
106.Xr dwarf_formsig8 3 ,
107.Xr dwarf_formstring 3 ,
108.Xr dwarf_formudata 3 ,
109.Xr dwarf_hasattr 3
110