xref: /freebsd/contrib/elftoolchain/libdwarf/dwarf_expr_current_offset.3 (revision ae500c1ff8974130f7f2692772cf288b90349e0d)
1.\" Copyright (c) 2011 Kai Wang
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25.\" $Id: dwarf_expr_current_offset.3 3640 2018-10-14 14:09:13Z jkoshy $
26.\"
27.Dd September 13, 2011
28.Dt DWARF_EXPR_CURRENT_OFFSET 3
29.Os
30.Sh NAME
31.Nm dwarf_expr_current_offset
32.Nd retrieve the number of bytes in a location expression stream
33.Sh LIBRARY
34.Lb libdwarf
35.Sh SYNOPSIS
36.In libdwarf.h
37.Ft "Dwarf_Unsigned"
38.Fo dwarf_expr_current_offset
39.Fa "Dwarf_P_Expr expr"
40.Fa "Dwarf_Error *err"
41.Fc
42.Sh DESCRIPTION
43Function
44.Fn dwarf_expr_current_offset
45returns the size in bytes of the stream representation of a location
46expression.
47.Pp
48Argument
49.Ar expr
50should reference a location expression descriptor allocated using
51.Xr dwarf_new_expr 3 .
52.Pp
53If argument
54.Ar err
55is not NULL, it will be used to store error information in case
56of an error.
57.Sh RETURN VALUES
58On success, function
59.Fn dwarf_expr_current_offset
60returns the size in bytes of the location descriptor's stream
61representation.
62In case of an error, function
63.Fn dwarf_expr_current_offset
64returns
65.Dv DW_DLV_NOCOUNT
66and sets the argument
67.Ar err .
68.Sh ERRORS
69Function
70.Fn dwarf_expr_current_offset
71can fail with:
72.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT"
73.It Bq Er DW_DLE_ARGUMENT
74Argument
75.Ar expr
76was NULL.
77.El
78.Sh SEE ALSO
79.Xr dwarf 3 ,
80.Xr dwarf_add_expr_addr 3 ,
81.Xr dwarf_add_expr_addr_b 3 ,
82.Xr dwarf_add_expr_gen 3 ,
83.Xr dwarf_expr_into_block 3 ,
84.Xr dwarf_new_expr 3
85