1.\" $NetBSD: gelf_getsym.3,v 1.6 2024/03/03 17:37:34 christos Exp $ 2.\" 3.\" Copyright (c) 2006,2008 Joseph Koshy. All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 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 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 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 17.\" are disclaimed. in no event shall Joseph Koshy be liable 18.\" for any direct, indirect, incidental, special, exemplary, or consequential 19.\" damages (including, but not limited to, procurement of substitute goods 20.\" or services; loss of use, data, or profits; or business interruption) 21.\" however caused and on any theory of liability, whether in contract, strict 22.\" liability, or tort (including negligence or otherwise) arising in any way 23.\" out of the use of this software, even if advised of the possibility of 24.\" such damage. 25.\" 26.\" Id: gelf_getsym.3 3958 2022-03-12 14:31:32Z jkoshy 27.\" 28.Dd April 22, 2019 29.Dt GELF_GETSYM 3 30.Os 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.Fa 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.Fa 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.Fa ndx 71in data buffer 72.Fa data 73and copies it to the destination pointed to by argument 74.Fa 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.Fa sym 82to class-dependent form, and writes it to the symbol entry at index 83.Fa ndx 84in the data buffer described by argument 85.Fa 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.Fa sym 96if successful, or 97.Dv NULL 98in case of an error. 99Function 100.Fn gelf_update_sym 101returns a non-zero value if successful, or zero in case of an error. 102.Sh ERRORS 103These functions may fail with the following errors: 104.Bl -tag -width "[ELF_E_RESOURCE]" 105.It Bq Er ELF_E_ARGUMENT 106Arguments 107.Fa data 108or 109.Fa sym 110were 111.Dv NULL . 112.It Bq Er ELF_E_ARGUMENT 113Argument 114.Fa ndx 115was less than zero or larger than the number of symbols in the data 116descriptor. 117.It Bq Er ELF_E_ARGUMENT 118Data descriptor 119.Fa data 120was not associated with a section containing symbol information. 121.It Bq Er ELF_E_RANGE 122A value was not representable in the target type. 123.It Bq Er ELF_E_VERSION 124The 125.Vt Elf_Data 126descriptor denoted by argument 127.Fa data 128is associated with an ELF object with an unsupported version. 129.El 130.Sh SEE ALSO 131.Xr elf 3 , 132.Xr elf_getdata 3 , 133.Xr elf_getscn 3 , 134.Xr gelf 3 , 135.Xr gelf_getsyminfo 3 , 136.Xr gelf_update_syminfo 3 137