1.\"	$NetBSD: dwarf_fde_cfa_offset.3,v 1.2 2014/03/09 16:58:03 christos Exp $
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3.\" Copyright (c) 2011 Kai Wang
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27.\" Id: dwarf_fde_cfa_offset.3 2073 2011-10-27 03:30:47Z jkoshy
28.\"
29.Dd September 26, 2011
30.Os
31.Dt DWARF_FDE_CFA_OFFSET 3
32.Sh NAME
33.Nm dwarf_fde_cfa_offset
34.Nd add a DW_CFA_offset frame instruction to a DWARF frame descriptor
35.Sh LIBRARY
36.Lb libdwarf
37.Sh SYNOPSIS
38.In libdwarf.h
39.Ft "Dwarf_P_Fde"
40.Fo dwarf_fde_cfa_offset
41.Fa "Dwarf_P_Fde fde"
42.Fa "Dwarf_Unsigned reg"
43.Fa "Dwarf_Signed offset"
44.Fa "Dwarf_Error *err"
45.Fc
46.Sh DESCRIPTION
47Function
48.Fn dwarf_fde_cfa_offset
49appends a
50.Dv DW_CFA_offset
51frame instruction to the frame descriptor referenced by argument
52.Ar fde .
53.Pp
54Argument
55.Ar fde
56should reference a frame descriptor allocated using
57.Xr dwarf_new_fde 3 .
58.Pp
59Argument
60.Ar reg
61specifies the register operand for the frame instruction.
62.Pp
63Argument
64.Ar offset
65specifies the offset operand for the frame instruction.
66.Pp
67If argument
68.Ar err
69is not NULL, it will be used to store error information in case of an
70error.
71.Sh RETURN VALUES
72On success, function
73.Fn dwarf_fde_cfa_offset
74returns the frame descriptor given in argument
75.Ar fde .
76In case of an error, function
77.Fn dwarf_fde_cfa_offset
78returns
79.Dv DW_DLV_BADADDR
80and sets the argument
81.Ar err .
82.Sh ERRORS
83Function
84.Fn dwarf_fde_cfa_offset
85can fail with:
86.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT"
87.It Bq Er DW_DLE_ARGUMENT
88Argument
89.Ar fde
90was NULL.
91.It Bq Er DW_DLE_MEMORY
92An out of memory condition was encountered during the execution of the
93function.
94.El
95.Sh SEE ALSO
96.Xr dwarf 3 ,
97.Xr dwarf_add_fde_inst 3 ,
98.Xr dwarf_add_frame_fde 3 ,
99.Xr dwarf_add_frame_fde_b 3 ,
100.Xr dwarf_add_frame_cie 3 ,
101.Xr dwarf_new_fde 3
102