xref: /freebsd/contrib/elftoolchain/libelf/elf_version.3 (revision fed1ca4b719c56c930f2259d80663cd34be812bb)
1.\" Copyright (c) 2006,2008 Joseph Koshy.  All rights reserved.
2.\"
3.\" Redistribution and use in source and binary forms, with or without
4.\" modification, are permitted provided that the following conditions
5.\" are met:
6.\" 1. Redistributions of source code must retain the above copyright
7.\"    notice, this list of conditions and the following disclaimer.
8.\" 2. Redistributions in binary form must reproduce the above copyright
9.\"    notice, this list of conditions and the following disclaimer in the
10.\"    documentation and/or other materials provided with the distribution.
11.\"
12.\" This software is provided by Joseph Koshy ``as is'' and
13.\" any express or implied warranties, including, but not limited to, the
14.\" implied warranties of merchantability and fitness for a particular purpose
15.\" are disclaimed.  in no event shall Joseph Koshy be liable
16.\" for any direct, indirect, incidental, special, exemplary, or consequential
17.\" damages (including, but not limited to, procurement of substitute goods
18.\" or services; loss of use, data, or profits; or business interruption)
19.\" however caused and on any theory of liability, whether in contract, strict
20.\" liability, or tort (including negligence or otherwise) arising in any way
21.\" out of the use of this software, even if advised of the possibility of
22.\" such damage.
23.\"
24.\" $Id: elf_version.3 2123 2011-11-09 15:40:09Z jkoshy $
25.\"
26.Dd November 9, 2011
27.Os
28.Dt ELF_VERSION 3
29.Sh NAME
30.Nm elf_version
31.Nd retrieve or set ELF library operating version
32.Sh LIBRARY
33.Lb libelf
34.Sh SYNOPSIS
35.In libelf.h
36.Ft unsigned int
37.Fn elf_version "unsigned int version"
38.Sh DESCRIPTION
39The
40.Fn elf_version
41function is used to query the current operating version of the ELF
42library, and to inform the ELF library about the application's desired
43operating version.
44.Pp
45If the argument
46.Ar version
47is
48.Dv EV_NONE ,
49the
50.Fn elf_version
51function returns the currently configured operating version for the
52ELF library.
53.Pp
54If the argument
55.Ar version
56is not
57.Dv EV_NONE ,
58and if argument
59.Ar version
60is supported by the ELF library, function
61.Fn elf_version
62sets the library's operating version to
63.Ar version ,
64and returns the previous value of the operating version.
65If argument
66.Ar version
67cannot be supported, then the
68.Fn elf_version
69function returns
70.Dv EV_NONE .
71.Sh RETURN VALUES
72The
73.Fn elf_version
74function returns the currently configured ELF library version, or
75.Dv EV_NONE
76if an unsupported version is requested.
77.Sh EXAMPLES
78An application program would inform the ELF library about its desired
79operating version and check for an error using the following code
80snippet:
81.Bd -literal -offset indent
82if (elf_version(EV_CURRENT) == EV_NONE)
83	err(EXIT_FAILURE, "ELF library too old");
84.Ed
85.Sh ERRORS
86Function
87.Fn elf_version
88may fail with the following error:
89.Bl -tag -width "[ELF_E_RESOURCE]"
90.It Bq Er "ELF_E_VERSION"
91An unsupported library version number was requested.
92.El
93.Sh SEE ALSO
94.Xr elf 3 ,
95.Xr gelf 3
96