


DD(1L)                                                     DD(1L)


NNAAMMEE
       dd - convert a file while copying it

SSYYNNOOPPSSIISS
       dddd  [if=file] [of=file] [ibs=bytes] [obs=bytes] [bs=bytes]
       [cbs=bytes]  [skip=blocks]  [seek=blocks]   [count=blocks]
       [conv={ascii,ebcdic,ibm,block,unblock,lcase,ucase,swab,noerror,notrunc,
       sync}]

DDEESSCCRRIIPPTTIIOONN
       This manual page documents the  GNU  version  of  dddd.   dddd
       copies  a  file  (from  the standard input to the standard
       output, by  default)  with  a  user-selectable  blocksize,
       while optionally performing conversions on it.

   OOPPTTIIOONNSS
       Numbers can be followed by a multiplier:
       b=512, k=1024, w=2, xm=number m

       _i_f_=_f_i_l_e
              Read from _f_i_l_e instead of the standard input.

       _o_f_=_f_i_l_e
              Write  to  _f_i_l_e  instead  of  the  standard output.
              Unless _c_o_n_v_=_n_o_t_r_u_n_c is given, truncate _f_i_l_e to  the
              size  specified  by  _s_e_e_k_= (0 bytes if _s_e_e_k_= is not
              given).

       _i_b_s_=_b_y_t_e_s
              Read _b_y_t_e_s bytes at a time.

       _o_b_s_=_b_y_t_e_s
              Write _b_y_t_e_s bytes at a time.

       _b_s_=_b_y_t_e_s
              Read and write _b_y_t_e_s bytes at atime.  Override  ibs
              and obs.

       _c_b_s_=_b_y_t_e_s
              Convert _b_y_t_e_s bytes at a time.

       _s_k_i_p_=_b_l_o_c_k_s
              Skip _b_l_o_c_k_s ibs-sized blocks at start of input.

       _s_e_e_k_=_b_l_o_c_k_s
              Skip _b_l_o_c_k_s obs-sized blocks at start of output.

       _c_o_u_n_t_=_b_l_o_c_k_s
              Copy only _b_l_o_c_k_s ibs-sized input blocks.

       _c_o_n_v_=_c_o_n_v_e_r_s_i_o_n_[_,_c_o_n_v_e_r_s_i_o_n_._._._]
              Convert  the  file  as  specified by the _c_o_n_v_e_r_s_i_o_n
              arguments.
              Conversions:



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DD(1L)                                                     DD(1L)


              ascii  Convert EBCDIC to ASCII.

              ebcdic Convert ASCII to EBCDIC.

              ibm    Convert ASCII to alternate EBCDIC.

              block  Pad newline-terminated records  to  size  of
                     cbs, replacing newline with trailing spaces.

              unblock
                     Replace trailing spaces in  cbs-sized  block
                     with newline.

              lcase  Change uppercase characters to lowercase.

              ucase  Change lowercase characters to uppercase.

              swab   Swap  every pair of input bytes.  Unlike the
                     Unix dd, this works when an  odd  number  of
                     bytes  are read.  If the input file contains
                     an odd number of bytes,  the  last  byte  is
                     simply  copied  (since  there  is nothing to
                     swap it with).

              noerror
                     Continue after read errors.

              sync   Pad every input block to size  of  ibs  with
                     trailing NULs.




























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