.\" Copyright (c) 2011 Kai Wang
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.\" $Id: dwarf_add_AT_reference.3 2072 2011-10-27 03:26:49Z jkoshy $
.\"
.Dd September 4, 2011
.Os
.Dt DWARF_ADD_AT_REFERENCE 3
.Sh NAME
.Nm dwarf_add_AT_reference
.Nd create and attach an attribute that references another DIE
.Sh LIBRARY
.Lb libdwarf
.Sh SYNOPSIS
.In libdwarf.h
.Ft "Dwarf_P_Attribute"
.Fo dwarf_add_AT_reference
.Fa "Dwarf_P_Debug dbg"
.Fa "Dwarf_P_Die die"
.Fa "Dwarf_Half attr"
.Fa "Dwarf_P_Die ref_die"
.Fa "Dwarf_Error *err"
.Fc
.Sh DESCRIPTION
Function
.Fn dwarf_add_AT_reference
creates an attribute descriptor that references another debugging
information entry in the same compilation unit.
The attribute will be of DWARF form
.Dv DW_FORM_ref4
or
.Dv DW_FORM_ref8
depending on the target address size, and will contain the
section-relative offset of the referenced debugging information entry
as its value.
.Pp
Argument
.Ar dbg
should reference a DWARF producer instance allocated using
.Xr dwarf_producer_init 3
or
.Xr dwarf_producer_init_b 3 .
.Pp
Argument
.Ar die
should reference a debugging information entry allocated using
.Xr dwarf_new_die 3 .
.Pp
Argument
.Ar attr
should specify the attribute code of the created attribute descriptor.
.Pp
Argument
.Ar ref_die
should hold the debugging information entry descriptor that
the attribute should refer to.
.Pp
If argument
.Ar err
is not NULL, it will be used to store error information in case
of an error.
.Sh RETURN VALUES
On success, function
.Fn dwarf_add_AT_reference
returns the created attribute descriptor.
In case of an error, function
.Fn dwarf_add_AT_reference
returns
.Dv DW_DLV_BADADDR
and sets the argument
.Ar err .
.Sh ERRORS
Function
.Fn dwarf_add_AT_reference
can fail with:
.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT"
.It Bq Er DW_DLE_ARGUMENT
One of the arguments
.Ar dbg ,
.Ar die
or
.Ar ref_die
was NULL.
.It Bq Er DW_DLE_MEMORY
An out of memory condition was encountered during the execution of
the function.
.El
.Sh SEE ALSO
.Xr dwarf 3 ,
.Xr dwarf_add_AT_dataref 3 ,
.Xr dwarf_add_AT_ref_address 3 ,
.Xr dwarf_add_AT_signed_const 3 ,
.Xr dwarf_add_AT_unsigned_const 3 ,
.Xr dwarf_new_die 3 ,
.Xr dwarf_producer_init 3 ,
.Xr dwarf_producer_init_b 3