man pages for uudecode

NAME
     uuencode, uudecode - encode a binary  file,  or  decode  its
     encoded representation

SYNOPSIS
     uuencode [ source-file ]  decode_pathname

     uudecode [ -p ]  [ encoded-file ]

DESCRIPTION
  uuencode
     uuencode converts a binary file into an encoded  representa-
     tion that can be sent using mail(1). It encodes the contents
     of source-file, or the  standard  input  if  no  source-file
     argument is given.
      The   decode_pathname    argument    is    required.    The
     decode_pathname  is included in the encoded file's header as
     the name of the file into which uudecode  is  to  place  the
     binary (decoded) data. uuencode also includes the permission
     modes of source-file, (except  setuid , setgid, and  sticky-
     bits),  so that decode_pathname is recreated with those same
     permission modes.

  uudecode
     uudecode reads an encoded-file, strips off any  leading  and
     trailing  lines  added by mailer programs, and recreates the
     original binary data with the filename and the  mode  speci-
     fied in the header.

     The encoded file is an ordinary portable character set  text
     file;  it  can be edited by any text editor. It is best only
     to change the mode or   decode_pathname  in  the  header  to
     avoid corrupting the decoded binary.

OPTIONS
  uudecode
     -p    decode encoded-file and send it  to  standard  output.
           This allows uudecode to be used in a pipeline.

OPERANDS
  uuencode
     The following operands are supported by  uuencode:

     decode_pathname
           The pathname of the file into which the uudecode util-
           ity  will place the decoded file. If there are charac-
           ters in decode_pathname that are not in  the  portable
           filename character set the results are unspecified.

     source-file
           A pathname of the file to be encoded.

  uudecode
     The following operand is supported by uudecode:

     encoded-file
           The pathname of a file containing the output of  uuen-
           code.

USAGE
     See largefile(5) for the  description  of  the  behavior  of
     uuencode  and  uudecode when encountering files greater than
     or equal to 2 Gbyte ( 2**31 bytes).

ENVIRONMENT VARIABLES
     See environ(5) for descriptions of the following environment
     variables   that   affect  the  execution  of  uuencode  and
     uudecode: LC_CTYPE, LC_MESSAGES, and NLSPATH.

OUTPUT
  stdout
     The standard output is a text file (encoded in the character
     set of the current locale) that begins with the line:

          "begin%s%s\n", , decode_pathname

     and ends with the line:

          end\n

     In both cases, the lines have no preceding or trailing blank
     characters.

     The algorithm that is used for lines in  between  begin  and
     end  takes  three octets as input and writes four characters
     of output by splitting the input at six-bit  intervals  into
     four  octets,  containing  data  in the lower six bits only.
     These octets are converted to characters by adding  a  value
     of  0x20  to  each octet, so that each octet is in the range
     0x20-0x5f, and then it is assumed to represent  a  printable
     character. It then will be translated into the corresponding
     character codes for  the  codeset  in  use  in  the  current
     locale. (For example, the octet 0x41, representing A , would
     be translated to A in the current codeset, such as  0xc1  if
     it were EBCDIC.)

     Where the bits of two octets are combined, the least  signi-
     ficant bits of the first octet are shifted left and combined
     with the most significant bits of the second  octet  shifted
     right.  Thus the three octets A, B, C are converted into the
     four octets:

          0x20 + (((A << 4)  ((B >> 4) & 0xF)) & 0x3F)
          0x20 + (((B << 2)  ((C >> 6) & 0x3)) & 0x3F)

     These octets are then translated into  the  local  character
     set.

     Each encoded line contains a length character, equal to  the
     number  of  characters to be decoded plus 0x20 translated to
     the local character set as described above, followed by  the
     encoded  characters.   The  maximum  number  of octets to be
     encoded on each line is 45.

EXIT STATUS
     The following exit values are returned:

     0     Successful completion.

     >0    An error occurred.

ATTRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:

     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | Availability                | SUNWesu                     |
    |_____________________________|_____________________________|

SEE ALSO
     mail(1), mailx(1), uucp(1C), uux(1C), attributes(5),  large-
     file(5)

NOTES
     The encoded file's size is expanded by 35% (3  bytes  become
     4,  plus  control information), causing it to take longer to
     transmit than the equivalent binary.

     The user on the remote system who is invoking uudecode (typ-
     ically  uucp)  must have write permission on the file speci-
     fied in the decode_pathname.

     If you uuencode then uudecode a file in the same  directory,
     you will overwrite the original file.