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cp(1)



dd(1)                          DG/UX 5.4R3.00                          dd(1)


NAME
       dd - convert and copy a file

SYNOPSIS
       dd [option=value] ...

DESCRIPTION
       Dd copies the specified input file to the specified output with
       possible conversions.  The standard input and output are used by
       default.  The input and output block size may be specified to take
       advantage of raw physical I/O.

       Option          Values
       if=file         Input file name; standard input is default
       of=file         Output file name; standard output is default
       ibs=n           Input block size n bytes (default 512)
       obs=n           Output block size (default 512)
       bs=n            Set both input and output block size, superseding ibs
                       and obs ; also, if no conversion is specified, it is
                       particularly efficient since no in-core copy need be
                       done
       cbs=n           Conversion buffer size
       skip=n          Skip n input blocks before starting copy
       iseek=n         Seek n blocks from beginning of input file before
                       copying
       oseek=n         Seek n blocks from beginning of output file before
                       copying
       count=n         Copy only n input blocks
       conv=ascii      Convert EBCDIC to ASCII
            ebcdic     Convert ASCII to EBCDIC
            ibm        Slightly different map of ASCII to EBCDIC
            lcase      Map alphabetics to lowercase
            ucase      Map alphabetics to uppercase
            swab       Swap every pair of bytes
            noerror    Do not stop processing on an error
            sync       Pad every input block to ibs
            ... , ...  Several comma-separated conversions
       files=n         Allows concatenation of multiple input files for tape
       conv=block      Convert to blocked files
       conv=unblock    Convert to unblocked files

       Where sizes are specified, the number of bytes is expected.  A number
       may end with k, b, or w to specify multiplication by 1024, 512, or 2,
       respectively; a pair of numbers may be separated by x to indicate a
       product.

       Cbs is used only if ascii or ebcdic conversion is specified.  In the
       former case, cbs characters are placed into the conversion buffer,
       converted to ASCII, trailing blanks trimmed, and new-line added
       before sending the line to the output.  In the latter case ASCII
       characters are read into the conversion buffer, converted to EBCDIC,
       and blanks added to make up an output block of size cbs.

       After completion, dd reports the number of whole and partial input



Licensed material--property of copyright holder(s)                         1




dd(1)                          DG/UX 5.4R3.00                          dd(1)


       and output blocks.

EXAMPLES
       To convert a file from lowercase to uppercase:

       $ cat file1
       this file contains only lower case letters.
       $ dd if=file1 of=file2 conv=ucase
       $ cat file2
       THIS FILE CONTAINS ONLY LOWER CASE LETTERS.
       $

       To write file0, file1, and file2 to magnetic tape:

       $ dd if=file0 of=/dev/rmt/0n conv=sync
       $ dd if=file1 of=/dev/rmt/0n conv=sync
       $ dd if=file2 of=/dev/rmt/0 conv=sync

DIAGNOSTICS
       f+p blocks in(out)  Numbers of full and partial blocks read(written)

SEE ALSO
       cp(1).

NOTES
       The ASCII/EBCDIC conversion tables are taken from the 256-character
       standard in the CACM Nov, 1968.  These do not always correspond to
       certain IBM® print train conventions.  There is no universal
       solution.

       New-lines are inserted only on conversion to ASCII; padding is done
       only on conversion to EBCDIC.  These should be separate options.

























Licensed material--property of copyright holder(s)                         2


Typewritten Software • bear@typewritten.org • Edmonds, WA 98026