1.\" $NetBSD: elf_rand.3,v 1.2 2014/03/09 16:58:04 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: elf_rand.3 189 2008-07-20 10:38:08Z jkoshy 27.\" 28.Dd June 17, 2006 29.Os 30.Dt ELF_RAND 3 31.Sh NAME 32.Nm elf_rand 33.Nd provide sequential access to the next archive member 34.Sh LIBRARY 35.Lb libelf 36.Sh SYNOPSIS 37.In libelf.h 38.Ft off_t 39.Fn elf_rand "Elf *archive" "off_t offset" 40.Sh DESCRIPTION 41The 42.Fn elf_rand 43function causes the ELF descriptor 44.Ar archive 45to be adjusted so that the next call to 46.Xr elf_begin 3 47will provide access to the archive member at byte offset 48.Ar offset 49in the archive. 50Argument 51.Ar offset 52is the byte offset from the start of the archive to the beginning of 53the archive header for the desired member. 54.Pp 55Archive member offsets may be retrieved using the 56.Xr elf_getarsym 3 57function. 58.Sh RETURN VALUES 59Function 60.Fn elf_rand 61returns 62.Ar offset 63if successful or zero in case of an error. 64.Sh EXAMPLES 65To process all the members of an archive use: 66.Bd -literal -offset indent 67off_t off; 68Elf *archive, *e; 69\&... 70cmd = ELF_C_READ; 71archive = elf_begin(fd, cmd, NULL); 72while ((e = elf_begin(fd, cmd, archive)) != (Elf *) 0) 73{ 74 ... process `e' here ... 75 elf_end(e); 76 77 off = ...new value...; 78 if (elf_rand(archive, off) != off) { 79 ... process error ... 80 } 81} 82elf_end(archive); 83.Ed 84.Pp 85To rewind an archive, use: 86.Bd -literal -offset indent 87Elf *archive; 88\&... 89if (elf_rand(archive, SARMAG) != SARMAG) { 90 ... error ... 91} 92.Ed 93.Sh ERRORS 94Function 95.Fn elf_rand 96may fail with the following errors: 97.Bl -tag -width "[ELF_E_RESOURCE]" 98.It Bq Er ELF_E_ARGUMENT 99Argument 100.Ar archive 101was null. 102.It Bq Er ELF_E_ARGUMENT 103Argument 104.Ar archive 105was not a descriptor for an 106.Xr ar 1 107archive. 108.It Bq Er ELF_E_ARCHIVE 109Argument 110.Ar offset 111did not correspond to the start of an archive member header. 112.El 113.Sh SEE ALSO 114.Xr ar 1 , 115.Xr elf 3 , 116.Xr elf_begin 3 , 117.Xr elf_end 3 , 118.Xr elf_getarsym 3 , 119.Xr elf_next 3 , 120.Xr gelf 3 121