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    The following form allows you to view linux man pages.

    Command:

    hd

    
                 [-s skip] file ...
         hd [-bcdovx] [-e format_string] [-f format_file] [-n length] [-s skip]
                 file ...
    
    
    

    DESCRIPTION

         The hexdump utility is a filter which displays the specified files, or
         the standard input, if no files are specified, in a user specified for-
         mat.
    
         The options are as follows:
    
         -b      One-byte octal display.  Display the input offset in hexadecimal,
                 followed by sixteen space-separated, three column, zero-filled,
                 bytes of input data, in octal, per line.
    
         -c      One-byte character display.  Display the input offset in hexadec-
                 imal, followed by sixteen space-separated, three column, space-
                 filled, characters of input data per line.
    
         -C      Canonical hex+ASCII display.  Display the input offset in hex-
                 adecimal, followed by sixteen space-separated, two column, hex-
                 adecimal bytes, followed by the same sixteen bytes in %_p format
                 enclosed in ''|'' characters.
    
                 Calling the command hd implies this option.
    
         -d      Two-byte decimal display.  Display the input offset in hexadeci-
                 mal, followed by eight space-separated, five column, zero-filled,
                 two-byte units of input data, in unsigned decimal, per line.
    
         -e format_string
                 Specify a format string to be used for displaying data.
    
         -f format_file
                 Specify a file that contains one or more newline separated format
                 strings.  Empty lines and lines whose first non-blank character
                 is a hash mark (#) are ignored.
    
         -n length
                 Interpret only length bytes of input.
    
         -o      Two-byte octal display.  Display the input offset in hexadecimal,
                 followed by eight space-separated, six column, zero-filled, two
                 byte quantities of input data, in octal, per line.
    
         -s offset
                 Skip offset bytes from the beginning of the input.  By default,
                 offset is interpreted as a decimal number.  With a leading 0x or
                 0X, offset is interpreted as a hexadecimal number, otherwise,
                 with a leading 0, offset is interpreted as an octal number.
                 Appending the character b, k, or m to offset causes it to be
                 interpreted as a multiple of 512, 1024, or 1048576, respectively.
    
         by the -e and -f options, in the order that they were specified.
    
       Formats
         A format string contains any number of format units, separated by whites-
         pace.  A format unit contains up to three items: an iteration count, a
         byte count, and a format.
    
         The iteration count is an optional positive integer, which defaults to
         one.  Each format is applied iteration count times.
    
         The byte count is an optional positive integer.  If specified it defines
         the number of bytes to be interpreted by each iteration of the format.
    
         If an iteration count and/or a byte count is specified, a single slash
         must be placed after the iteration count and/or before the byte count to
         disambiguate them.  Any whitespace before or after the slash is ignored.
    
         The format is required and must be surrounded by double quote (" ")
         marks.  It is interpreted as a fprintf-style format string (see
         fprintf(3)), with the following exceptions:
    
               ?   An asterisk (*) may not be used as a field width or precision.
    
               ?   A byte count or field precision is required for each ''s'' con-
                   version character (unlike the fprintf(3) default which prints
                   the entire string if the precision is unspecified).
    
               ?   The conversion characters ''%'', ''h'', ''l'', ''n'', ''p'' and
                   ''q'' are not supported.
    
               ?   The single character escape sequences described in the C stan-
                   dard are supported:
    
                         NUL                  \0
                         <alert character>    \a
                         <backspace>          \b
                         <form-feed>          \f
                         <newline>            \n
                         <carriage return>    \r
                         <tab>                \t
                         <vertical tab>       \v
    
         The hexdump utility also supports the following additional conversion
         strings:
    
         _a[dox]     Display the input offset, cumulative across input files, of
                     the next byte to be displayed.  The appended characters d, o,
                     and x specify the display base as decimal, octal or hexadeci-
                     mal respectively.
    
         _A[dox]     Identical to the _a conversion string except that it is only
                     performed once, when all of the input data has been pro-
                     played as hexadecimal strings.
    
                     000 NUL  001 SOH  002 STX  003 ETX  004 EOT  005 ENQ
                     006 ACK  007 BEL  008 BS   009 HT   00A LF   00B VT
                     00C FF   00D CR   00E SO   00F SI   010 DLE  011 DC1
                     012 DC2  013 DC3  014 DC4  015 NAK  016 SYN  017 ETB
                     018 CAN  019 EM   01A SUB  01B ESC  01C FS   01D GS
                     01E RS   01F US   07F DEL
    
         The default and supported byte counts for the conversion characters are
         as follows:
    
               %_c, %_p, %_u, %c       One byte counts only.
    
               %u, %X, %x'                        Four byte default, one, two and
                                       four byte counts supported.
    
               %G, %g' %f,                    Eight byte default, four and twelve
                                       byte counts supported.
    
         The amount of data interpreted by each format string is the sum of the
         data required by each format unit, which is the iteration count times the
         byte count, or the iteration count times the number of bytes required by
         the format if the byte count is not specified.
    
         The input is manipulated in ''blocks'', where a block is defined as the
         largest amount of data specified by any format string.  Format strings
         interpreting less than an input block's worth of data, whose last format
         unit both interprets some number of bytes and does not have a specified
         iteration count, have the iteration count incremented until the entire
         input block has been processed or there is not enough data remaining in
         the block to satisfy the format string.
    
         If, either as a result of user specification or hexdump modifying the
         iteration count as described above, an iteration count is greater than
         one, no trailing whitespace characters are output during the last itera-
         tion.
    
         It is an error to specify a byte count as well as multiple conversion
         characters or strings unless all but one of the conversion characters or
         strings is _a or _A.
    
         If, as a result of the specification of the -n option or end-of-file
         being reached, input data only partially satisfies a format string, the
         input block is zero-padded sufficiently to display all available data
         (i.e., any format units overlapping the end of data will display some
         number of the zero bytes).
    
         Further output by such format strings is replaced by an equivalent number
         of spaces.  An equivalent number of spaces is defined as the number of
         spaces output by an s conversion character with the same field width and
         precision as the original conversion character or conversion string but
               "\t\t" "%_p "
               "\n"
    
         Implement the -x option:
    
               "%07.7_Ax\n"
               "%07.7_ax  " 8/2 "%04x " "\n"
    
         Some examples for the -e option:
    
               # hex bytes
               % echo hello | hexdump -v -e '/1 "%02X "' ; echo
               68 65 6C 6C 6F 0A
    
               # same, with ASCII section
               % echo hello | hexdump -e '8/1 "%02X ""\t"" "' -e '8/1 "%c""\n"'
               68 65 6C 6C 6F 0A        hello
    
               # hex with preceding 'x'
               % echo hello | hexdump -v -e '"x" 1/1 "%02X" " "' ; echo
               x68 x65 x6C x6C x6F x0A
    
               # one hex byte per line
               % echo hello | hexdump -v -e '/1 "%02X\n"'
               68
               65
               6C
               6C
               6F
               0A
    
               # a table of byte#, hex, decimal, octal, ASCII
               % echo hello | hexdump -v  -e '/1  "%_ad#    "' -e '/1    "%02X hex"' -e '/1 " = %03i dec"' -e '/1 " = %03o oct"' -e '/1 " = _%c\_\n"'
               0#    68 hex = 104 dec = 150 oct = _h_
               1#    65 hex = 101 dec = 145 oct = _e_
               2#    6C hex = 108 dec = 154 oct = _l_
               3#    6C hex = 108 dec = 154 oct = _l_
               4#    6F hex = 111 dec = 157 oct = _o_
               5#    0A hex = 010 dec = 012 oct = _
               _
    
               # byte# & ASCII with control chars
               % echo hello | hexdump -v  -e '/1  "%_ad#  "' -e '/1 " _%_u\_\n"'
               0#   _h_
               1#   _e_
               2#   _l_
               3#   _l_
               4#   _o_
               5#   _lf_
    
    
    

    SEE ALSO

         gdb(1), od(1)
    
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