uuencode man page

uuencode — encode a file into email friendly text


uuencode [-flags] [-flag [value]] [--option-name[[=| ]value]] [<in-file>] <output-name>


uuencode is used to create an ASCII representation of a file that can be sent over channels that may otherwise corrupt the data. Specifically, email cannot handle binary data and will often even insert a character when the six character sequence "0rom " is seen.

uuencode will read in-file if provided and otherwise read data from standard in and write the encoded form to standard out. The output will begin with a header line for use by uudecode giving it the resulting suggested file output-name and access mode. If the output-name is specifically /dev/stdout, then uudecode will emit the decoded file to standard out.

Note: uuencode uses buffered input and assumes that it is not hand typed from a tty. The consequence is that at a tty, you may need to hit Ctl-D several times to terminate input.


-m, --base64
convert using base64.

By default, uuencode will encode using the traditional conversion. It is slower and less compact than base64. The encoded form of the file is expanded by 37% for UU encoding and by 35% for base64 encoding (3 bytes become 4 plus control information).
-e, --encode-file-name
encode the output file name.

Since output file names may contain characters that are not handled well by various transmission modes, you may specify that the output-name be base64 encoded as well. (Traditional uuencoding of the file name is not supported.)
-h, --help
Display usage information and exit.
-!, --more-help
Pass the extended usage information through a pager.
-R [cfgfile], --save-opts [=cfgfile]
Save the option state to cfgfile. The default is the last configuration file listed in the Option Presets section, below. The command will exit after updating the config file.
-r cfgfile, --load-opts=cfgfile, --no-load-opts
Load options from cfgfile. The no-load-opts form will disable the loading of earlier config/rc/ini files. --no-load-opts is handled early, out of order.
-v [{v|c|n --version [{v|c|n}]}]
Output version of program and exit. The default mode is `v', a simple version. The `c' mode will print copyright information and `n' will print the full copyright notice.

Option Presets

Any option that is not marked as not presettable may be preset by loading values from configuration ("RC" or ".INI") file(s). The file "$HOME/.sharrc" will be used, if present.


This implementation is compliant with P1003.2b/D11.


See Option Presets for configuration files.

Exit Status

One of the following exit values will be returned:

Successful program execution.
The operation failed or the command syntax was not valid.
A specified configuration file could not be loaded.
libopts had an internal operational error. Please report it to autogen-users@lists.sourceforge.net. Thank you.

See Also

uudecode(1), uuencode(5)


The uuencode command first appeared in BSD 4.0.


Free Software Foundation, Inc.


Please put sharutils in the subject line for emailed bug reports. It helps to spot the message.

Please send bug reports to: bug-gnu-utils@gnu.org


This manual page was AutoGen-erated from the uuencode option definitions.

Referenced By

a64l(3), e2fsck(8), haveged(8), libarchive(3), libarchive-formats(5), suffixes(7), uudecode(1), uudeview(1), uuencode(5), uuencode(n), uuenview(1), xdeview(1), xxd(1).

Explore man page connections for uuencode(1).

GNU sharutils (4.15.2) 30 May 2015