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: gelf_getdyn.3 3734 2019-04-22 14:10:49Z jkoshy $ 25.\" 26.Dd April 22, 2019 27.Dt GELF_GETDYN 3 28.Os 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.It Bq Er ELF_E_VERSION 119The 120.Vt Elf_Data 121descriptor denoted by argument 122.Ar data 123is associated with an ELF object with an unsupported version. 124.El 125.El 126.Sh SEE ALSO 127.Xr elf 3 , 128.Xr elf_getdata 3 , 129.Xr elf_getscn 3 , 130.Xr gelf 3 131