xref: /freebsd/usr.bin/bintrans/uuencode.format.5 (revision bdcbfde31e8e9b343f113a1956384bdf30d1ed62)

.\" Copyright (c) 1989, 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.Dd January 12, 1994
.Dt UUENCODE 5
.Os
.Sh NAME
.Nm uuencode
.Nd format of an encoded uuencode file
.Sh DESCRIPTION
Files output by
.Xr uuencode 1
consist of a header line,
followed by a number of body lines,
and a trailer line.
The
.Xr uudecode 1
command
will ignore any lines preceding the header or
following the trailer.
Lines preceding a header must not, of course,
look like a header.
.Pp
The header line is distinguished by having the first
6 characters
.Dq begin\ \&
(note the trailing space).
The word
.Em begin
is followed by a mode (in octal),
and a string which names the remote file.
A space separates the three items in the header line.
.Pp
The body consists of a number of lines, each at most 62 characters
long (including the trailing newline).
These consist of a character count,
followed by 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 1 to 45 or 64 and can
be determined by subtracting the character space (octal 40)
from the character.
Character 64 represents a count of zero.
.Pp
Groups of 3 bytes are stored in 4 characters, 6 bits per character.
All characters are always in range from 1 to 64 and are offset by a
space (octal 40) to make the characters printing.
Character
64 represents a count of zero.
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 null characters will be included to make the character count a multiple
of 4.
The body is terminated by a line with a count of zero.
This line consists of one
.Tn ASCII
backquote (octal 140) character.
.Pp
The trailer line consists of
.Dq end
on a line by itself.
.Sh SEE ALSO
.Xr mail 1 ,
.Xr uucp 1 ,
.Xr uudecode 1 ,
.Xr uuencode 1
.Sh HISTORY
The
.Nm
file format appeared in
.Bx 4.0 .
.\" It was named uuencode.5 prior to 4.3