XDELTA3(1)

✨ XDELTA3 ✨

okay bestie, sit DOWN because today we're talking about xdelta3, a binary diff tool that runs on the VCDIFF (RFC 3284) format plus compression 💅 it's the girl who finds the differences between two files and makes them smol. no cap.

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🌸 SYNOPSIS 🌸

xdelta3 [command] [options] [input [output]]

like. give her a command, some options, an input, an output. she'll handle it 🫶

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💖 DESCRIPTION 💖

xdelta3 is a binary diff tool that uses the VCDIFF (RFC 3284) format and compression. that's it, that's the whole vibe. binary diffs, iconic format, compressed, slay 🔥

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👑 COMMANDS 👑

• config — prints xdelta3 configuration. show me ur settings queen 💅
• decode — decompress the input, also set by -d
• encode — compress the input, also set by -e (this is the default one, the main character ⭐)
• test — run the builtin tests. she's testing herself, as she should 🧚
• printdelta — print information about the entire delta
• printhdr — print information about the first window
• printhdrs — print information about all windows
• recode — encode with new application/secondary settings

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🎀 OPTIONS 🎀

standard options:

• -0 .. -9 — compression level. pick ur level, girl 💜
• -c — use stdout
• -d — decompress
• -e — compress
• -f — force overwrite. she WILL overwrite, no questions 🙈
• -F — force the external-compression subprocess
• -h — show help
• -q — be quiet 🤫
• -v — be verbose (max 2). two is the limit bestie, don't push it
• -V — show version

memory options:

• -B — bytes source window size
• -W — bytes input window size
• -P — size compression duplicates window
• -I — size instruction buffer size (0 = unlimited)

compression options:

• -s — source source file to copy from (if any)
• -S [djw|fgk] — enable/disable secondary compression
• -N — disable small string-matching compression
• -D — disable external decompression (encode/decode)
• -R — disable external recompression (decode)
• -n — disable checksum (encode/decode)
• -C — soft config (encode, undocumented). literally undocumented, we know nothing, she's mysterious ✨
• -A [apphead] — disable/provide application header (encode)
• -J — disable output (check/compute only)
• -T — use alternate code table (test)
• -m — arguments for "merge"

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🦋 NOTES 🦋

the XDELTA environment variable may contain extra args, and honestly that's her little superpower:

XDELTA="-s source-x.y.tar.gz" \
tar --use-compress-program=xdelta3 -cf \
target-x.z.tar.gz.vcdiff target-x.y/

look at her go 😭💖

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🌈 EXAMPLES 🌈

compress the differences between SOURCE and TARGET, yielding OUT, using "djw" secondary compression:

xdelta3 -S djw -s SOURCE TARGET OUT

do the same, using standard input and output:

xdelta3 -S djw -s SOURCE < TARGET > OUT

to decompress OUT, using SOURCE, yielding TARGET:

xdelta3 -d -s SOURCE OUT TARGET

three examples, all iconic, all ate 💅

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💜 AUTHOR 💜

xdelta3 was written by Josh MacDonald <josh.macdonald@gmail.com>.

this manual page was written by Leo 'costela' Antunes <costela@debian.org> for the Debian project (but may be used by others). give her her flowers fr fr 🌸

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that's the whole page bestie, go compress something 🫶

okay and one last thing — this was the xdelta3 page from the Xdelta3 manual, dated August 2013, living in section XDELTA3(1) of the general commands manual. mwah 💋