Linux Pocket Guide

Name

uuencode [options] newfile infile — sharutils

Synopsis

/usr/bin stdin stdout - file -- opt --help --version

Before the days of email attachments and MIME, binary files took some work to transmit by email. You would first uuencode the files (pronounced “you-you-encode”) into an ASCII format that looks like this:

begin 644 myfile
M(R`N8F%S:%]P<F]F:6QE"B,@4G5N<R!F:7)S="!W:&5N(&QO9V=I;F<@:6X@
M=6YD97(@1TY/344*"G1R87`@)PH@('1E<W0@+6X@(B134TA?04=%3E1?4$E$
...
end

Upon receiving this data, the recipient would uudecode (“you-you-decode”) it to restore the original data.

To convert a file myfile into uuencoded format, creating myfile.uu:

$ uuencode newfile myfile > myfile.uu

The first argument, newfile, is the file to be created at decoding time. It will appear in the first line of uuencoded output:

begin 644 newfile
M(R`N8F%S:%]P<F]F:6QE"B,@4G5N<R!F:7)S="!W:&5N(&QO9V=I;F<@:6X@
...

To decode this uudecoded file myfile.uu, creating newfile:

$ uudecode myfile.uu