uuencode(5) - man - phpman

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Encode binary files into ASCII for transport via mediums that only support simple ASCII encoding.

Encode a file and print the result to `stdout`
uuencode {{path/to/input_file}} {{output_file_name_after_decoding}}
Encode a file and write the result to a file
uuencode -o {{path/to/output_file}} {{path/to/input_file}} {{output_file_name_after_decoding}}
Encode a file using Base64 instead of the default uuencode encoding and write the result to a file
uuencode {{-m|--base64}} -o {{path/to/output_file}} {{path/to/input_file}} {{output_file_name_after_decoding}}

UUENCODE(5) File Formats Manual UUENCODE(5)

NAME
uuencode - format of an encoded uuencode file

DESCRIPTION
Files output by uuencode(1) consist of a header line, followed by a number of body lines, and
a trailer line. The uudecode(1) command will ignore any lines preceding the header or fol‐
lowing the trailer. Lines preceding a header must not, of course, look like a header.

The header line is distinguished by having the first 5 characters be begin followed by a
space, or else a hyphen and either base64 or encoded or both (also separated with a hyphen).
The base64 option says the file has been encoded using base64. The encoded option says the
output file name has been base64 encoded. It is never encoded with traditional uuencoding.
This is a GNU extension. These are followed by a mode (in octal), and a string which names
the remote file. The mode is separated from the begin clause and the file name by a single
space character.

Traditional uuencoding
The traditional uuencoded file body consists of a number of lines, each at most 62 characters
long (including the trailing newline). These consist of a character count letter, followed by
the encoded characters, followed by a newline. The character count is a single printing
character, and represents an integer, the number of bytes the rest of the line represents.
Such integers are always in the range from 0 to 63 and can be determined by subtracting the
character space (octal 40) from the character.

Groups of 3 bytes are stored in 4 characters, 6 bits per character. All are offset by a
space to make the characters printing. The last line may be shorter than the normal 45
bytes. If the size is not a multiple of 3, this fact can be determined by the value of the
count on the last line. Extra garbage will be included to make the character count a multi‐
ple of 4. The body is terminated by a line with a count of zero. This line consists of one
ASCII space.

The trailer line consists of end on a line by itself.

base64 encoding
base64 encoded files follow the specified format for the body, but also include a begin-
base64 header and a trailer line of four = characters.

EXAMPLES
begin-base64-encoded 644 VE9ETw==
This introduces a base64 encoded file named, TODO with that name encoded using base64 encod‐
ing.

begin-encoded 644 5$]$3P``
This introduces an encoded file named, TODO with that name encoded using uuencoding. The en‐
coding is a lot less friendly. Please prefer base64 encoding.

CONFORMING TO
IEEE Std 1003.1, plus extensions

The -encoded suffix to the begin header line is a GNU extension. Recipients must have the
GNU uudecode program to decode them.

SEE ALSO
uuencode(1), uudecode(1), base64(1GNU)

HISTORY
The uuencode file format appeared in BSD 4.0 .

UUENCODE(5)