BASE91(1)

🌸 NAME 🌸

Okay bestie, meet base91(1) from the General Commands Manual — the little tool that basE91-encodes or decodes FILE, or standard input, and sends it straight to standard output. Slay. ✨

🦋 SYNOPSIS 🦋

base91 [-d|--decode] [-o|--output] [-m|--buffer] [-v|--verbose]... [-w|--wrap] [--simd] [-h|--help] [-V|--version] [FILE]

✨ DESCRIPTION ✨

The whole point, fr fr: basE91 encode or decode FILE, or standard input, to standard output. 💖

No FILE? Or FILE is literally -? Then it reads standard input, bestie. Easy.

💅 OPTIONS 💅

• -d, --decode — Flip it to decode instead of encode. The format is auto-detected. SIMD streams are checked strictly: a byte outside the alphabet, a broken line layout, or an invalid length is an error, reported with its offset (exit status 1). Legacy streams ignore bytes outside their alphabet, just like the C reference does. 🕵️‍♀️
• -o, --output <FILE> — Write output to FILE instead of standard output. 💾
• -m, --buffer <SIZE> — Use SIZE bytes of memory for I/O buffers. Suffixes: b, K, M. Default: 64K. 🧺
• -v, --verbose — Verbose mode: print statistics to stderr. Repeat it (-vv) for extra verbosity. 🗣️
• -w, --wrap <COLS> — Wrap encoded lines after COLS characters (0 = no wrap; default 76, or 64 with --simd, where COLS must be a multiple of 32). Has no effect when decoding. 🎀
• --simd — Use the SIMD fixed-width variant for encoding. Output begins with - and uses the SIMD alphabet (0x23-0x26, 0x28-0x7E); not compatible with legacy Henke decoders. The format is auto-detected at decode time, so plain -d works for both SIMD and Henke streams. Output contains no single-quote characters and is safe to single-quote in shell. Ignored when decoding. With --wrap, the value must be a multiple of 32. ⚡
• -h, --help — Print help (the page literally says: see a summary with -h). 🙋‍♀️
• -V, --version — Print version. 🏷️
• [FILE] — Input file (default: stdin). 📥

Bestie, if you’re decoding a SIMD stream, it is strict — one bad byte and it’s over. The error message names the problem and its byte offset, and you get exit status 1. 💀

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🎀 EXTRA 🎀

🍓 Examples 🍓

Copy-paste these bad boys, bestie:

base91 file.bin > file.b91            encode binary file
base91 -d file.b91 > file.bin         decode
b91enc < file.bin > file.b91          encode with no line wrapping
b91dec < file.b91 > file.bin          decode
base91 --simd file.bin > file.b91s    encode with SIMD variant
tar czf - dir/ | b91enc               encode tar stream

💀 Exit status 💀

• 0 — success. Iconic. 👑
• 1 — an error, including an invalid SIMD stream when decoding. The message names the error and its byte offset. 😭

🌈 VERSION 🌈

v0.3.2 — that’s the version, bestie. ✨

👑 AUTHORS 👑

Algorithm by Joachim Henke; Rust port by Frederic Ruget. 🫶

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That’s the whole manual moment: base91 version 0.3.2, hanging out in the User Commands section, and the footer has no date listed — so we are absolutely not inventing one. Periodt. 💖