uuencode, uudecode, b64encode, b64decode - encode/decode a
uuencode [-m] [-o output_file] [file] name
uudecode [-cimprs] [file ...]
uudecode [-i] -o output_file
b64encode [-o output_file] [file] name
b64decode [-ciprs] [file ...]
b64decode [-i] -o output_file [file]
The uuencode and uudecode utilities are used to transmit binary files
over transmission mediums that do not support formats other
ASCII data. b64encode and b64decode are equivalent to
uuencode and uudecode 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
the mode of the file and the operand name for use by
uudecode transforms ``uuencoded'' files (or by default, the
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 set-user-ID and execute bits are
not retained. uudecode ignores any leading and trailing
The options for uuencode are as follows:
-m Use the Base64 method of encoding, rather than the
Output to output_file instead of standard output.
The options for uudecode are as follows:
-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.
Output to output_file instead of any pathname contained in the input
-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
uudecode deletes any prefix ending with the last
slash '/' for security
The following example packages up a source tree, compresses
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 email@example.com
The following example unpacks all uuencoded files from your
your current working directory.
$ uudecode -c < $MAIL
The following example extracts a compressed tar archive from
$ uudecode -o /dev/stdout > $MAIL | zcat | tar xfv -
basename(1), compress(1), mail(1), uuencode(5)
The uudecode and uuencode utilities conform to IEEE Std
The uudecode and uuencode utilities appeared in 4.0BSD.
Files encoded using the traditional algorithm are expanded
by 35% (3
bytes become 4 plus control information).
OpenBSD 3.6 January 27, 2002
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