1.\"	$NetBSD: dwarf_hasattr.3,v 1.2 2014/03/09 16:58:04 christos Exp $
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3.\" Copyright (c) 2010 Kai Wang
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27.\" Id: dwarf_hasattr.3 2073 2011-10-27 03:30:47Z jkoshy
28.\"
29.Dd April 17, 2010
30.Os
31.Dt DWARF_HASATTR 3
32.Sh NAME
33.Nm dwarf_hasattr
34.Nd check for the presence of an attribute
35.Sh LIBRARY
36.Lb libdwarf
37.Sh SYNOPSIS
38.In libdwarf.h
39.Ft int
40.Fo dwarf_hasattr
41.Fa "Dwarf_Die die"
42.Fa "Dwarf_Half attr"
43.Fa "Dwarf_Bool *ret_bool"
44.Fa "Dwarf_Error *err"
45.Fc
46.Sh DESCRIPTION
47Function
48.Fn dwarf_hasattr
49tests whether the debugging information entry referenced in argument
50.Ar die
51contains the attribute named by argument
52.Ar attr .
53Legal values for argument
54.Ar attr
55are those denoted by the
56.Dv DW_AT_*
57constants in the DWARF specification.
58.Pp
59If the named attribute is present in the debugging information entry,
60function
61.Fn dwarf_hasattr
62returns a non-zero value in the location pointed to by argument
63.Ar ret_bool .
64If the named attribute is not present, a zero is written instead.
65.Pp
66If argument
67.Ar err
68is not NULL, it will be used to return an error descriptor in case
69of an error.
70.Sh RETURN VALUES
71On success, function
72.Fn dwarf_hasattr
73returns
74.Dv DW_DLV_OK .
75In case of an error, it returns
76.Dv DW_DLV_ERROR
77and sets argument
78.Ar err .
79.Sh ERRORS
80Function
81.Fn dwarf_hasattr
82can fail with the following error:
83.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT"
84.It Bq Er DW_DLE_ARGUMENT
85Either of argument
86.Va die
87or
88.Va ret_bool
89was NULL.
90.Sh SEE ALSO
91.Xr dwarf 3 ,
92.Xr dwarf_attr 3 ,
93.Xr dwarf_whatattr 3
94