BINTRANS(1)

💖 NAME 💖

okay so bestie, welcome to BINTRANS(1) from the General Commands Manual — this is the group chat for encoding and decoding binary files. The whole fam is bintrans, uuencode, uudecode, b64encode, b64decode, and base64, and their job is literally encode / decode a binary file. slay. 💅

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✨ SYNOPSIS ✨

bintrans [algorithm] [...]
uuencode [-m] [-r] [-o output_file] [file] name
uudecode [-cimprs] [file ...]
uudecode [-i] -o output_file
b64encode [-r] [-w column] [-o output_file] [file] name
b64decode [-cimprs] [file ...]
b64decode [-i] -o output_file [file]
base64 [-h | -D | -d] [-b count] [-i input_file] [-o output_file]

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🦋 DESCRIPTION 🦋

The uuencode and uudecode utilities are the OGs for transmitting binary files over transmission mediums that do not support other than simple ASCII data. no cap, that’s the whole reason they exist. 🫶

The b64encode utility is synonymous with uuencode with the -m flag specified. The b64decode utility is synonymous with uudecode with the -m flag specified. matching set, iconic behavior. ✨

The base64 utility acts as a base64 decoder when passed the --decode (or -d) flag and as a base64 encoder otherwise. As a decoder it only accepts raw base64 input, and as an encoder it does not produce the framing lines. base64 reads standard input or file if it is provided and writes to standard output. Options --wrap (or -w) and --ignore-garbage (or -i) are accepted for compatibility with GNU base64, but the latter is unimplemented and silently ignored 🙈.

The uuencode utility reads file (or by default the standard input) and writes an encoded version to the standard output, or output_file if one has been specified. The encoding uses only printing ASCII characters and includes the mode of the file and the operand name for use by uudecode.

The uudecode utility transforms uuencoded files (or by default, the standard input) into the original form. The resulting file is named either name or (depending on options passed to uudecode) output_file and will have the mode of the original file except that setuid and execute bits are not retained. The uudecode utility ignores any leading and trailing lines.

💅 Options for uuencode 💅

The following options are available for uuencode:

• -m — Use the Base64 method of encoding, rather than the traditional uuencode algorithm.
• -r — Produce raw output by excluding the initial and final framing lines.
• -o output_file — Output to output_file instead of standard output.

🌸 Options for uudecode 🌸

The following options are available for uudecode:

• -c — Decode more than one uuencoded file from file if possible.
• -i — Do not overwrite files.
• -m — When used with the -r flag, decode Base64 input instead of traditional uuencode input. Without -r it has no effect.
• -o output_file — Output to output_file instead of any pathname contained in the input data.
• -p — Decode file and write output to standard output.
• -r — Decode raw (or broken) input, which is missing the initial and possibly the final framing lines. The input is assumed to be in the traditional uuencode encoding, but if the -m flag is used, or if the utility is invoked as b64decode, then the input is assumed to be in Base64 format.
• -s — Do not strip output pathname to base filename. By default uudecode deletes any prefix ending with the last slash '/' for security reasons.

🎀 Extra b64encode option 🎀

Additionally, b64encode accepts the following option:

• -w column — Wrap encoded output after column.

🧚 Options for base64 🧚

The following options are available for base64:

• -b count, --break=count — Insert line breaks every count characters. The default is 0, which generates an unbroken stream.
• -d, -D, --decode — Decode incoming Base64 stream into binary data.
• -h, --help — Print usage summary and exit.
• -i input_file, --input=input_file — Read input from input_file. The default is stdin; passing "-" also represents stdin.
• -o output_file, --output=output_file — Write output to output_file. The default is stdout; passing "-" also represents stdout.

bintrans is a generic utility that can run any of the aforementioned encoders and decoders. It can also run algorithms that are not available through a dedicated program:

qp is a quoted-printable converter and accepts the following options:

• -u — Decode.
• -o output_file — Output to output_file instead of standard output.

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🔥 EXAMPLES 🔥

The following example packages up a source tree, compresses it, uuencodes it and mails it to a user on another system. When uudecode is run on the target system, the file src_tree.tar.Z will be created which may then be uncompressed and extracted into the original tree.

tar cf - src_tree | compress |
uuencode src_tree.tar.Z | mail user@example.com

The following example unpacks all uuencoded files from your mailbox into your current working directory.

uudecode -c < $MAIL

The following example extracts a compressed tar archive from your mailbox

uudecode -o /dev/stdout < $MAIL | zcat | tar xfv -

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👑 SEE ALSO 👑

go check out basename(1), compress(1), mail(1), uucp(1) (that one lives in ports/net/freebsd-uucp, iykyk), and uuencode(5). the whole friend group, fr fr. 🫶

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⭐ HISTORY ⭐

The uudecode and uuencode utilities appeared in 4.0BSD. vintage icons only. 💜

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💀 BUGS 💀

Files encoded using the traditional algorithm are expanded by 35% (3 bytes become 4 plus control information). not me doing the math and crying 😭. that’s just how it is, bestie.

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kisses and glitter, this page came from Debian, dated January 23, 2024, for BINTRANS(1) 🫶✨💅