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