xref: /minix3/external/bsd/elftoolchain/dist/libelf/gelf_getsym.3 (revision 0a6a1f1d05b60e214de2f05a7310ddd1f0e590e7)
1.\"	$NetBSD: gelf_getsym.3,v 1.2 2014/03/09 16:58:04 christos Exp $
2.\"
3.\" Copyright (c) 2006,2008 Joseph Koshy.  All rights reserved.
4.\"
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6.\" modification, are permitted provided that the following conditions
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8.\" 1. Redistributions of source code must retain the above copyright
9.\"    notice, this list of conditions and the following disclaimer.
10.\" 2. Redistributions in binary form must reproduce the above copyright
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14.\" This software is provided by Joseph Koshy ``as is'' and
15.\" any express or implied warranties, including, but not limited to, the
16.\" implied warranties of merchantability and fitness for a particular purpose
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26.\" Id: gelf_getsym.3 189 2008-07-20 10:38:08Z jkoshy
27.\"
28.Dd August 29, 2006
29.Os
30.Dt GELF_GETSYM 3
31.Sh NAME
32.Nm gelf_getsym ,
33.Nm gelf_update_sym
34.Nd read and update symbol information
35.Sh LIBRARY
36.Lb libelf
37.Sh SYNOPSIS
38.In gelf.h
39.Ft "GElf_Sym *"
40.Fn gelf_getsym "Elf_Data *data" "int ndx" "GElf_Sym *sym"
41.Ft int
42.Fn gelf_update_sym "Elf_Data *data" "int ndx" "GElf_Sym *sym"
43.Sh DESCRIPTION
44These convenience functions are used to retrieve and update class-dependent
45.Vt Elf32_Sym
46and
47.Vt Elf64_Sym
48structures in 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_SYMTAB ,
56.Dv SHT_DYNSYM
57or
58.Dv SHT_GNU_versym .
59Argument
60.Ar ndx
61is the index of the symbol being retrieved or updated.
62The class-independent
63.Vt GElf_Sym
64structure is described in
65.Xr gelf 3 .
66.Pp
67Function
68.Fn gelf_getsym
69retrieves class-dependent symbol information at index
70.Ar ndx
71in data buffer
72.Ar data
73and copies it to the destination pointed to by argument
74.Ar sym
75after translation to class-independent form.
76.Pp
77Function
78.Fn gelf_update_sym
79converts the class-independent symbol information pointed to
80by argument
81.Ar sym
82to class-dependent form, and writes it to the symbol entry at index
83.Ar ndx
84in the data buffer described by argument
85.Ar data .
86Function
87.Fn gelf_update_sym
88signals an error if any of the values in the class-independent
89representation exceeds the representable limits of the target
90type.
91.Sh RETURN VALUES
92Function
93.Fn gelf_getsym
94returns the value of argument
95.Ar sym
96if successful, or NULL in case of an error.
97Function
98.Fn gelf_update_sym
99returns a non-zero value if successful, or zero in case of an error.
100.Sh ERRORS
101These functions may fail with the following errors:
102.Bl -tag -width "[ELF_E_RESOURCE]"
103.It Bq Er ELF_E_ARGUMENT
104Arguments
105.Ar data
106or
107.Ar sym
108were NULL.
109.It Bq Er ELF_E_ARGUMENT
110Argument
111.Ar ndx
112was less than zero or larger than the number of symbols in the data
113descriptor.
114.It Bq Er ELF_E_ARGUMENT
115Data descriptor
116.Ar data
117was not associated with a section containing symbol information.
118.It Bq Er ELF_E_RANGE
119A value was not representable in the target type.
120.El
121.Sh SEE ALSO
122.Xr elf 3 ,
123.Xr elf_getdata 3 ,
124.Xr elf_getscn 3 ,
125.Xr gelf 3 ,
126.Xr gelf_getsyminfo 3 ,
127.Xr gelf_update_syminfo 3
128