1.\"- 2.\" Copyright 2003-2005 Colin Percival 3.\" All rights reserved 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted providing 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 THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 16.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 18.\" 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, 22.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 23.\" IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 24.\" POSSIBILITY OF SUCH DAMAGE. 25.\" 26.\" $FreeBSD$ 27.\" 28.Dd May 18, 2003 29.Dt BSDIFF 1 30.Os 31.Sh NAME 32.Nm bsdiff 33.Nd "generate a patch between two binary files" 34.Sh SYNOPSIS 35.Nm 36.Ar oldfile newfile patchfile 37.Sh DESCRIPTION 38The 39.Nm 40utility 41compares 42.Ar oldfile 43to 44.Ar newfile 45and writes to 46.Ar patchfile 47a binary patch suitable for use by 48.Xr bspatch 1 . 49When 50.Ar oldfile 51and 52.Ar newfile 53are two versions of an executable program, the 54patches produced are on average a factor of five smaller 55than those produced by any other binary patch tool known 56to the author. 57.Pp 58The 59.Nm 60utility 61uses memory equal to 17 times the size of 62.Ar oldfile , 63and requires 64an absolute minimum working set size of 8 times the size of 65.Ar oldfile . 66.Sh SEE ALSO 67.Xr bspatch 1 68.Sh AUTHORS 69.An Colin Percival Aq Mt cperciva@FreeBSD.org 70.Sh BUGS 71The 72.Nm 73utility does not store the hashes of 74.Ar oldfile 75or 76.Ar newfile 77in 78.Ar patchfile . 79As a result, it is possible to apply a patch to the wrong file; this 80will usually produce garbage. 81It is recommended that users of 82.Nm 83store the hashes of 84.Ar oldfile 85and 86.Ar newfile 87and compare against them before and after applying 88.Ar patchfile . 89