encode/decode a binary file
uudecode utilities are used to transmit binary files
over transmission mediums that do not support formats other than printable
b64decode are equivalent to running
respectively with the
-m flag specified.
uuencode reads file
(or by default, the standard input) and writes an encoded version to the
standard output, or to output_file if it has been
specified. The encoding uses only printing ASCII characters and includes the
mode of the file and the operand name for use by
“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
output_file and will have the mode of the original
file except that set-user-ID and execute bits are not retained.
uudecode ignores any leading and trailing lines.
The options for
uuencode are as
- Use the Base64 method of encoding, rather than the traditional
- Output to output_file instead of standard output.
The options for
uudecode are as
- Decode more than one uuencoded file from file if possible.
- Do not overwrite files.
- When used with the
-rflag, decode Base64 input instead of traditional
-rit has no effect.
- Output to output_file instead of any pathname contained in the input data.
- Decode file and write output to standard output.
- 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
uuencodeencoding, but if the
-mflag is used, or if the utility is invoked as
b64decode, then the input is assumed to be in Base64 format.
- Do not strip output pathname to base filename. By default
uudecodedeletes any prefix ending with the last slash '/' for security reasons.
b64decode utilities exit 0 on success,
and >0 if an error occurs.
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 firstname.lastname@example.org
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 -
basename(1), compress(1), mail(1), uuencode(5)
uuencode utilities are compliant with the
IEEE Std 1003.1-2008 (“POSIX.1”)
The flags [
-ciprs] are extensions to that
The use of the
-o flag for
uuencode and the
-m flag for
uudecode are also extensions to that
uuencode utilities appeared in
Files encoded using the traditional algorithm are expanded by 35% (3 bytes become 4 plus control information).