.\" Copyright (c) 2010 Kai Wang
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.\" $Id: dwarf_hasattr.3 3181 2015-04-10 13:22:51Z emaste $
.\"
.Dd April 17, 2010
.Os
.Dt DWARF_HASATTR 3
.Sh NAME
.Nm dwarf_hasattr
.Nd check for the presence of an attribute
.Sh LIBRARY
.Lb libdwarf
.Sh SYNOPSIS
.In libdwarf.h
.Ft int
.Fo dwarf_hasattr
.Fa "Dwarf_Die die"
.Fa "Dwarf_Half attr"
.Fa "Dwarf_Bool *ret_bool"
.Fa "Dwarf_Error *err"
.Fc
.Sh DESCRIPTION
Function
.Fn dwarf_hasattr
tests whether the debugging information entry referenced in argument
.Ar die
contains the attribute named by argument
.Ar attr .
Legal values for argument
.Ar attr
are those denoted by the
.Dv DW_AT_*
constants in the DWARF specification.
.Pp
If the named attribute is present in the debugging information entry,
function
.Fn dwarf_hasattr
returns a non-zero value in the location pointed to by argument
.Ar ret_bool .
If the named attribute is not present, a zero is written instead.
.Pp
If argument
.Ar err
is not NULL, it will be used to return an error descriptor in case
of an error.
.Sh RETURN VALUES
On success, function
.Fn dwarf_hasattr
returns
.Dv DW_DLV_OK .
In case of an error, it returns
.Dv DW_DLV_ERROR
and sets argument
.Ar err .
.Sh ERRORS
Function
.Fn dwarf_hasattr
can fail with the following error:
.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT"
.It Bq Er DW_DLE_ARGUMENT
Either of argument
.Va die
or
.Va ret_bool
was NULL.
.El
.Sh SEE ALSO
.Xr dwarf 3 ,
.Xr dwarf_attr 3 ,
.Xr dwarf_whatattr 3