xref: /freebsd/contrib/elftoolchain/libelf/elf_version.3 (revision a7623790fb345e6dc986dfd31df0ace115e6f2e4)
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24.\" $Id: elf_version.3 3639 2018-10-14 14:07:02Z jkoshy $
25.\"
26.Dd November 9, 2011
27.Dt ELF_VERSION 3
28.Os
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