Ubuntu Manpage: diffoscope - in-depth comparison of files, archives, and directories

NAME

       diffoscope - in-depth comparison of files, archives, and directories

SYNOPSIS

       diffoscope --help
       diffoscope [OPTIONS] [--json output_diff] path1 path2
       diffoscope [OPTIONS] diff
       diffoscope [OPTIONS] < diff

DESCRIPTION

diffoscope will try to get to the bottom of what makes files or directories different. It will
recursively unpack archives of many kinds and transform various binary formats into more human readable
form to compare them. It can compare two tarballs, ISO images, or PDF just as easily.

It can be scripted through error codes, and a report can be produced with the detected differences. The
report can be text or HTML. When no type of report has been selected, diffoscope defaults to write a
text report on the standard output.

diffoscope was initially started by the "reproducible builds" Debian project and now being developed as
part of the (wider) ???Reproducible Builds??? initiative. It is meant to be able to quickly understand
why two builds of the same package produce different outputs. diffoscope was previously named debbindiff.

See the COMMAND-LINE EXAMPLES section further below to get you started, as well as more detailed
explanations of all the command-line options. The same information is also available in
/usr/share/doc/diffoscope/README.rst or similar.

positional arguments:
path1 First file or directory to compare. If omitted, tries to read a diffoscope diff from stdin.

path2 Second file or directory to compare. If omitted, no comparison is done but instead we read a
diffoscope diff from path1 and will output this in the formats specified by the rest of the
command line.

optional arguments:
--debug
Display debug messages

--debugger
Open the Python debugger in case of crashes

--status-fd FD
Send machine-readable status to file descriptor FD

--progress, --no-progress
Show an approximate progress bar. Default: yes if stdin is a tty, otherwise no.

--no-default-limits
Disable most default output limits and diff calculation limits.

output types:
--text OUTPUT_FILE
Write plain text output to given file (use - for stdout)

--text-color WHEN
When to output color diff. WHEN is one of {never, auto, always}. Default: auto, meaning yes if the
output is a terminal, otherwise no.

--output-empty
If there was no difference, then output an empty diff for each output type that was specified. In
--text output, an empty file is written.

--html OUTPUT_FILE
Write HTML report to given file (use - for stdout)

--html-dir OUTPUT_DIR
Write multi-file HTML report to given directory

--css URL
Link to an extra CSS for the HTML report

--jquery URL
URL link to jQuery, for --html and --html-dir output. If this is a non-existent relative URL,
diffoscope will create a symlink to a system installation. (Paths searched:
/usr/share/javascript/jquery/jquery.js.) If not given, --html output will not use JS but --htmldir
will if it can be found; give "disable" to disable JS on all outputs.

--json OUTPUT_FILE
Write JSON text output to given file (use - for stdout)

--markdown OUTPUT_FILE
Write Markdown text output to given file (use - for stdout)

--restructured-text OUTPUT_FILE
Write RsT text output to given file (use - for stdout)

--profile OUTPUT_FILE
Write profiling info to given file (use - for stdout)

output limits:
--max-text-report-size BYTES
Maximum bytes written in --text report. (0 to disable, default: 0)

--max-report-size BYTES
Maximum bytes of a report in a given format, across all of its pages. Note that some formats, such
as --html, may be restricted by even smaller limits such as --max-page-size. (0 to disable,
default: 41943040)

--max-diff-block-lines LINES
Maximum number of lines output per unified-diff block, across all pages. (0 to disable, default:
1024)

--max-page-size BYTES
Maximum bytes of the top-level (--html-dir) or sole (--html) page. (default: 409600, remains in
effect even with --no-default-limits)

--max-page-size-child BYTES
In --html-dir output, this is the maximum bytes of each child page (default: 204800, remains in
effect even with --no-default-limits)

--max-page-diff-block-lines LINES
Maximum number of lines output per unified-diff block on the top-level (--html-dir) or sole
(--html) page, before spilling it into child pages (--html-dir) or skipping the rest of the diff
block. Child pages are limited instead by --max-page-size-child. (default: 128, remains in effect
even with --no-default-limits)

diff calculation:
--new-file
Treat absent files as empty

--exclude GLOB_PATTERN
Exclude files that match GLOB_PATTERN. Use this option to ignore files based on their names.

--exclude-command REGEX_PATTERN
Exclude commands that match REGEX_PATTERN. For example '^readelf.*\s--debug-dump=info' can take a
long time and differences here are likely secondary differences caused by something represented
elsewhere. Use this option to disable commands that use a lot of resources.

--exclude-directory-metadata, --no-exclude-directory-metadata
Exclude directory metadata. Useful if comparing files whose filesystem-level metadata is not
intended to be distributed to other systems. This is true for most distributions package builders,
but not true for the output of commands such as `make install`. Metadata of archive members remain
un-excluded. Use this option to ignore permissions, timestamps, xattrs etc. Default: False if
comparing two directories, else True. Note that "file" metadata actually a property of its
containing directory, and is not relevant when distributing the file across systems.

--fuzzy-threshold FUZZY_THRESHOLD
Threshold for fuzzy-matching (0 to disable, 60 is default, 400 is high fuzziness)

--tool-prefix-binutils PREFIX
Prefix for binutils program names, e.g. "aarch64-linux-gnu-" for a foreign-arch binary or "g" if
you're on a non-GNU system.

--max-diff-input-lines LINES
Maximum number of lines fed to diff(1) (0 to disable, default: 4194304)

--max-container-depth DEPTH
Maximum depth to recurse into containers. (Cannot be disabled for security reasons, default: 50)

--max-diff-block-lines-saved LINES
Maximum number of lines saved per diff block. Most users should not need this, unless you run out
of memory. This truncates diff(1) output before emitting it in a report, and affects all types of
output, including --text and --json. (0 to disable, default: 0)

--force-details
Force recursing into the depths of file formats even if files have the same content, only really
useful for debugging diffoscope. Default: False

information commands:
--help, -h
Show this help and exit

--version
Show program's version number and exit

--list-tools [DISTRO]
Show external tools required and exit. DISTRO can be one of {arch, debian, FreeBSD}. If specified,
the output will list packages in that distribution that satisfy these dependencies.

--list-debian-substvars
List packages needed for Debian in 'substvar' format.

file formats supported:
- Android APK files.

- Android boot images.

- Ar(1) archives.

- Berkeley DB database files.

- Bzip2 archives.

- Character/block devices.

- ColorSync colour profiles (.icc).

- Coreboot CBFS filesystem images.

- Cpio archives.

- Dalvik .dex files.

- Debian .buildinfo files.

- Debian .changes files.

- Debian source packages (.dsc).

- Device Tree Compiler blob files.

- Directories.

- ELF binaries.

- Ext2/ext3/ext4/btrfs filesystems.

- FreeDesktop Fontconfig cache files.

- FreePascal files (.ppu).

- Gettext message catalogues.

- GHC Haskell .hi files.

- GIF image files.

- Git repositories.

- GNU R database files (.rdb).

- GNU R Rscript files (.rds).

- Gnumeric spreadsheets.

- Gzipped files.

- ISO 9660 CD images.

- Java .class files.

- JavaScript files.

- JPEG images.

- JSON files.

- LLVM IR bitcode files.

- MacOS binaries.

- Microsoft Windows icon files.

- Microsoft Word .docx files.

- Mono 'Portable Executable' files.

- Ogg Vorbis audio files.

- OpenOffice .odt files.

- OpenSSH public keys.

- OpenWRT package archives (.ipk).

- PDF documents.

- PGP signed/encrypted messages.

- PNG images.

- PostScript documents.

- RPM archives.

- Rust object files (.deflate).

- SQLite databases.

- SquashFS filesystems.

- Statically-linked binaries.

- Symlinks.

- Tape archives (.tar).

- Tcpdump capture files (.pcap).

- Text files.

- TrueType font files.

- XML binary schemas (.xsb).

- XML files.

- XZ compressed files.

EXIT STATUS

       Exit status is 0 if inputs are the same, 1 if different, 2 if trouble.

COMMAND-LINE EXAMPLES

       To compare two files in-depth and produce an HTML report, run something like:

          $ diffoscope --html output.html build1.changes build2.changes

       diffoscope will exit with 0 if there's no differences and 1 if there are.

       diffoscope can also compare non-existent files:

          $ diffoscope /nonexistent archive.zip

       To get all possible options, run:

          $ diffoscope --help

       If you have enough RAM, you can improve performance by running:

          $ TMPDIR=/run/shm diffoscope very-big-input-0/ very-big-input-1/

       By default this allowed to use up half of RAM; for more add something like:

          tmpfs   /run/shm    tmpfs   size=80%    0   0

       to your /etc/fstab; see man mount for details.

EXTERNAL DEPENDENCIES

       diffoscope requires Python 3 and the following modules available on PyPI: libarchive-c, python-magic.

       The various comparators rely on external commands being available. To get a list of them, please run:

          $ diffoscope --list-tools

CONTRIBUTORS

       Lunar, Reiner Herrmann, Chris Lamb, Mattia Rizzolo, Ximin Luo, Helmut Grohne, Holger Levsen, Daniel  Kahn
       Gillmor,  Paul  Gevers,  Peter  De Wachter, Yasushi SHOJI, Clemens Lang, Ed Maste, Joachim Breitner, Mike
       McQuaid. Baptiste Daroussin, Levente Polyak.

CONTACT

       Please report bugs and send patches through  the  Debian  bug  tracking  system  against  the  diffoscope
       package: <https://bugs.debian.org/src:diffoscope>

       For more instructions, see CONTRIBUTING.rst in this directory.

       Join the users and developers mailing-list: <https://lists.reproducible-builds.org/listinfo/diffoscope>

       diffoscope website is at <https://diffoscope.org/>

LICENSE

       diffoscope  is free software: you can redistribute it and/or modify it under the terms of the GNU General
       Public License as published by the Free Software Foundation, either version 3 of the License, or (at your
       option) any later version.

       diffoscope is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even  the
       implied  warranty  of  MERCHANTABILITY  or  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
       License for more details.

       You should have received a copy of the GNU General Public License along with diffoscope.  If not, see  <‐
       https://www.gnu.org/licenses/>.