xref: /freebsd/contrib/elftoolchain/libelf/gelf_getdyn.3 (revision 63a938566d524836885917d95bd491aa4400b181)
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24.\" $Id: gelf_getdyn.3 189 2008-07-20 10:38:08Z jkoshy $
25.\"
26.Dd August 29, 2006
27.Os
28.Dt GELF_GETDYN 3
29.Sh NAME
30.Nm gelf_getdyn ,
31.Nm gelf_update_dyn
32.Nd read and update ELF dynamic entries
33.Sh LIBRARY
34.Lb libelf
35.Sh SYNOPSIS
36.In gelf.h
37.Ft "GElf_Dyn *"
38.Fn gelf_getdyn "Elf_Data *data" "int ndx" "GElf_Dyn *dyn"
39.Ft int
40.Fn gelf_update_dyn "Elf_Data *data" "int ndx" "GElf_Dyn *dyn"
41.Sh DESCRIPTION
42These convenience functions are used to retrieve and update class-dependent
43.Vt Elf32_Dyn
44or
45.Vt Elf64_Dyn
46information in the
47.Sy dynamic
48table of an ELF object.
49.Pp
50Argument
51.Ar data
52is an
53.Vt Elf_Data
54descriptor associated with a section of type
55.Dv SHT_DYNAMIC .
56Argument
57.Ar ndx
58is the index of the entry being retrieved or updated.
59The class-independent
60.Vt GElf_Dyn
61structure is described in
62.Xr gelf 3 .
63.Pp
64Function
65.Fn gelf_getdyn
66retrieves the class-dependent entry at index
67.Ar ndx
68in data buffer
69.Ar data
70and copies it to the destination pointed to by argument
71.Ar dyn
72after translation to class-independent form.
73.Pp
74Function
75.Fn gelf_update_dyn
76converts the class-independent entry pointed to
77by argument
78.Ar dyn
79to class-dependent form, and writes it to the entry at index
80.Ar ndx
81in the data buffer described by argument
82.Ar data .
83Function
84.Fn gelf_update_dyn
85signals an error if any of the values in the class-independent
86representation exceeds the representable limits of the target
87type.
88.Sh RETURN VALUES
89Function
90.Fn gelf_getdyn
91returns the value of argument
92.Ar dyn
93if successful, or NULL in case of an error.
94Function
95.Fn gelf_update_dyn
96returns a non-zero value if successful, or zero in case of an error.
97.Sh ERRORS
98These functions may fail with the following errors:
99.Bl -tag -width "[ELF_E_RESOURCE]"
100.It Bq Er ELF_E_ARGUMENT
101Arguments
102.Ar data
103or
104.Ar dyn
105were NULL.
106.It Bq Er ELF_E_ARGUMENT
107Argument
108.Ar ndx
109was less than zero or larger than the number of entries in the data
110descriptor.
111.It Bq Er ELF_E_ARGUMENT
112Data descriptor
113.Ar data
114was not associated with a section of type
115.Dv SHT_DYNAMIC .
116.It Bq Er ELF_E_RANGE
117A value was not representable in the target type.
118.El
119.Sh SEE ALSO
120.Xr elf 3 ,
121.Xr elf_getdata 3 ,
122.Xr elf_getscn 3 ,
123.Xr gelf 3
124