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25.\" $Id: dwarf_hasattr.3 3640 2018-10-14 14:09:13Z jkoshy $
26.\"
27.Dd April 17, 2010
28.Dt DWARF_HASATTR 3
29.Os
30.Sh NAME
31.Nm dwarf_hasattr
32.Nd check for the presence of an attribute
33.Sh LIBRARY
34.Lb libdwarf
35.Sh SYNOPSIS
36.In libdwarf.h
37.Ft int
38.Fo dwarf_hasattr
39.Fa "Dwarf_Die die"
40.Fa "Dwarf_Half attr"
41.Fa "Dwarf_Bool *ret_bool"
42.Fa "Dwarf_Error *err"
43.Fc
44.Sh DESCRIPTION
45Function
46.Fn dwarf_hasattr
47tests whether the debugging information entry referenced in argument
48.Ar die
49contains the attribute named by argument
50.Ar attr .
51Legal values for argument
52.Ar attr
53are those denoted by the
54.Dv DW_AT_*
55constants in the DWARF specification.
56.Pp
57If the named attribute is present in the debugging information entry,
58function
59.Fn dwarf_hasattr
60returns a non-zero value in the location pointed to by argument
61.Ar ret_bool .
62If the named attribute is not present, a zero is written instead.
63.Pp
64If argument
65.Ar err
66is not NULL, it will be used to return an error descriptor in case
67of an error.
68.Sh RETURN VALUES
69On success, function
70.Fn dwarf_hasattr
71returns
72.Dv DW_DLV_OK .
73In case of an error, it returns
74.Dv DW_DLV_ERROR
75and sets argument
76.Ar err .
77.Sh ERRORS
78Function
79.Fn dwarf_hasattr
80can fail with the following error:
81.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT"
82.It Bq Er DW_DLE_ARGUMENT
83Either of argument
84.Va die
85or
86.Va ret_bool
87was NULL.
88.El
89.Sh SEE ALSO
90.Xr dwarf 3 ,
91.Xr dwarf_attr 3 ,
92.Xr dwarf_whatattr 3
93