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(textutils.info)od invocation

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`od': Write files in octal or other formats
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   `od' writes an unambiguous representation of each FILE (`-' means
standard input), or standard input if none are given.  Synopsis:

     od [OPTION]... [FILE]...
     od -C [FILE] [[+]OFFSET [[+]LABEL]]

   Each line of output consists of the offset in the input, followed by
groups of data from the file. By default, `od' prints the offset in
octal, and each group of file data is two bytes of input printed as a
single octal number.

   The program accepts the following options.  Also see Note: Common
options.

`-A RADIX'
`--address-radix=RADIX'
     Select the base in which file offsets are printed.  RADIX can be
     one of the following:

    `d'
          decimal;

    `o'
          octal;

    `x'
          hexadecimal;

    `n'
          none (do not print offsets).

     The default is octal.

`-j BYTES'
`--skip-bytes=BYTES'
     Skip BYTES input bytes before formatting and writing.  If BYTES
     begins with `0x' or `0X', it is interpreted in hexadecimal;
     otherwise, if it begins with `0', in octal; otherwise, in decimal.
     Appending `b' multiplies BYTES by 512, `k' by 1024, and `m' by
     1048576.

`-N BYTES'
`--read-bytes=BYTES'
     Output at most BYTES bytes of the input.  Prefixes and suffixes on
     `bytes' are interpreted as for the `-j' option.

`-s [N]'
`--strings[=N]'
     Instead of the normal output, output only "string constants": at
     least N (3 by default) consecutive ASCII graphic characters,
     followed by a null (zero) byte.

`-t TYPE'
`--format=TYPE'
     Select the format in which to output the file data.  TYPE is a
     string of one or more of the below type indicator characters.  If
     you include more than one type indicator character in a single TYPE
     string, or use this option more than once, `od' writes one copy of
     each output line using each of the data types that you specified,
     in the order that you specified.

     Adding a trailing "z" to any type specification appends a display
     of the ASCII character representation of the printable characters
     to the output line generated by the type specification.

    `a'
          named character,

    `c'
          ASCII character or backslash escape,

    `d'
          signed decimal,

    `f'
          floating point,

    `o'
          octal,

    `u'
          unsigned decimal,

    `x'
          hexadecimal.

     The type `a' outputs things like `sp' for space, `nl' for newline,
     and `nul' for a null (zero) byte.  Only the least significant
     seven bits of each byte will be used for this type specification.
     Type `c' outputs ` ', `\n', and `\0', respectively.

     Except for types `a' and `c', you can specify the number of bytes
     to use in interpreting each number in the given data type by
     following the type indicator character with a decimal integer.
     Alternately, you can specify the size of one of the C compiler's
     built-in data types by following the type indicator character with
     one of the following characters.  For integers (`d', `o', `u',
     `x'):

    `C'
          char,

    `S'
          short,

    `I'
          int,

    `L'
          long.

     For floating point (`f'):

    F
          float,

    D
          double,

    L
          long double.

`-v'
`--output-duplicates'
     Output consecutive lines that are identical.  By default, when two
     or more consecutive output lines would be identical, `od' outputs
     only the first line, and puts just an asterisk on the following
     line to indicate the elision.

`-w[N]'
`--width[=N]'
     Dump `n' input bytes per output line.  This must be a multiple of
     the least common multiple of the sizes associated with the
     specified output types.  If N is omitted, the default is 32.  If
     this option is not given at all, the default is 16.

   The next several options map the old, pre-POSIX format specification
options to the corresponding POSIX format specs.  GNU `od' accepts any
combination of old- and new-style options.  Format specification
options accumulate.

`-a'
     Output as named characters.  Equivalent to `-ta'.

`-b'
     Output as octal bytes.  Equivalent to `-toC'.

`-c'
     Output as ASCII characters or backslash escapes.  Equivalent to
     `-tc'.

`-d'
     Output as unsigned decimal shorts.  Equivalent to `-tu2'.

`-f'
     Output as floats.  Equivalent to `-tfF'.

`-h'
     Output as hexadecimal shorts.  Equivalent to `-tx2'.

`-i'
     Output as decimal shorts.  Equivalent to `-td2'.

`-l'
     Output as decimal longs.  Equivalent to `-td4'.

`-o'
     Output as octal shorts.  Equivalent to `-to2'.

`-x'
     Output as hexadecimal shorts.  Equivalent to `-tx2'.

`-C'
`--traditional'
     Recognize the pre-POSIX non-option arguments that traditional `od'
     accepted.  The following syntax:

          od --traditional [FILE] [[+]OFFSET[.][b] [[+]LABEL[.][b]]]

     can be used to specify at most one file and optional arguments
     specifying an offset and a pseudo-start address, LABEL.  By
     default, OFFSET is interpreted as an octal number specifying how
     many input bytes to skip before formatting and writing.  The
     optional trailing decimal point forces the interpretation of
     OFFSET as a decimal number.  If no decimal is specified and the
     offset begins with `0x' or `0X' it is interpreted as a hexadecimal
     number.  If there is a trailing `b', the number of bytes skipped
     will be OFFSET multiplied by 512.  The LABEL argument is
     interpreted just like OFFSET, but it specifies an initial
     pseudo-address.  The pseudo-addresses are displayed in parentheses
     following any normal address.