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Xdelta 3.x readme.txt Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015

Thanks for downloading Xdelta!

This directory contains the Xdelta3 command-line interface (CLI) and source distribution for VCDIFF differential compression, a.k.a. delta compression. The latest information and downloads are available here:

Xdelta can be configured to use XZ Utils for secondary compression:

The command-line syntax is detailed here:

Run 'xdelta3 -h' for brief help. Run 'xdelta3 test' for built-in tests.

Sample commands (like gzip, -e means encode, -d means decode)

xdelta3 -9 -S lzma -e -f -s OLD_FILE NEW_FILE DELTA_FILE xdelta3 -d -s OLD_FILE DELTA_FILE DECODED_FILE

File bug reports and browse open support issues here:

The source distribution contains the C/C++/Python APIs, Unix, Microsoft VC++ and Cygwin builds. Xdelta3 is covered under the terms of the GPL, see COPYING.

Commercial inquiries welcome, please contact