.\" Copyright (c) 2011 Kai Wang
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.\" $Id: dwarf_fde_cfa_offset.3 2073 2011-10-27 03:30:47Z jkoshy $
.\"
.Dd September 26, 2011
.Os
.Dt DWARF_FDE_CFA_OFFSET 3
.Sh NAME
.Nm dwarf_fde_cfa_offset
.Nd add a DW_CFA_offset frame instruction to a DWARF frame descriptor
.Sh LIBRARY
.Lb libdwarf
.Sh SYNOPSIS
.In libdwarf.h
.Ft "Dwarf_P_Fde"
.Fo dwarf_fde_cfa_offset
.Fa "Dwarf_P_Fde fde"
.Fa "Dwarf_Unsigned reg"
.Fa "Dwarf_Signed offset"
.Fa "Dwarf_Error *err"
.Fc
.Sh DESCRIPTION
Function
.Fn dwarf_fde_cfa_offset
appends a
.Dv DW_CFA_offset
frame instruction to the frame descriptor referenced by argument
.Ar fde .
.Pp
Argument
.Ar fde
should reference a frame descriptor allocated using
.Xr dwarf_new_fde 3 .
.Pp
Argument
.Ar reg
specifies the register operand for the frame instruction.
.Pp
Argument
.Ar offset
specifies the offset operand for the frame instruction.
.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_fde_cfa_offset
returns the frame descriptor given in argument
.Ar fde .
In case of an error, function
.Fn dwarf_fde_cfa_offset
returns
.Dv DW_DLV_BADADDR
and sets the argument
.Ar err .
.Sh ERRORS
Function
.Fn dwarf_fde_cfa_offset
can fail with:
.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT"
.It Bq Er DW_DLE_ARGUMENT
Argument
.Ar fde
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_fde_inst 3 ,
.Xr dwarf_add_frame_fde 3 ,
.Xr dwarf_add_frame_fde_b 3 ,
.Xr dwarf_add_frame_cie 3 ,
.Xr dwarf_new_fde 3