hd(1) UNIX System V(Application Compatibility Package) hd(1)
NAME
hd - display files in hexadecimal format
SYNOPSIS
hd [-format [-s offset] [-n count] [file]
DESCRIPTION
The hd command displays the contents of files in hexadecimal octal,
decimal and character formats. Control over the specification of ranges
of characters is also available. The default behavior is with the
following flags set: ``-abx -A''. This says that addresses (file
offsets) and bytes are printed in hexadecimal and that characters are
also printed. If no file argument is given, the standard input is read.
Options include:
-s offset Specify the beginning offset in the file where printing is to
begin. If no `file' argument is given, or if a seek fails
because the input is a pipe, `offset' bytes are read from the
input and discarded. Otherwise, a seek error will terminate
processing of the current file.
The offset may be given in decimal, hexadecimal (preceded by
`Ox'), or octal (preceded by a `0'). It is optionally followed
by one of the following multipliers: w, l, b, or k; for words
(2 bytes), long words (4 bytes), blocks (512 bytes), or K bytes
(1024 bytes). Note that this is the one case where "b" does
not stand for bytes. Since specifying a hexadecimal offset in
blocks would result in an ambiguous trailing `b', any offset
and multiplier may be separated by an asterisk (*).
-n count Specify the number of bytes to process. The count is in the
same format as offset, above.
Format Flags
Format flags may specify addresses, characters, bytes, words (2 bytes),
or longs (4 bytes) to be printed in hexadecimal, decimal, or octal. Two
special formats may also be indicated: test or ASCII. Format and base
specifiers amy be freely combined and repeated as desired in order to
specify different bases (hexadecimal, decimal or octal) for different
output formats (addresses, characters, etc.). All format flags appearing
in a single argument are applied as appropriate to all other flags in
that argument.
acbwlA Output format specifiers for address, characters, bytes, words,
longs and ASCII, respectively. Only one base specifier will be
used for addresses; the address will appear on the first line
of output that begins each new offset in the input.
The character format prints printable characters unchanged,
special C escapes as defined in the language, and remaining
values in the specified base.
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hd(1) UNIX System V(Application Compatibility Package) hd(1)
The ASCII format prints all printable characters unchanged, and
all others as a period (.). This format appears to the right
of the first of other specified output formats. A base
specifier has no meaning with the ASCII format. If no other
output format (other than addresses) is given, bx is assumed.
If no base specifier is given, all of xdo are used.
xdo Output base specifiers for hexadecimal, decimal and octal. If
no format specifier is given, all of acbwl are used.
t Print a test file, each line preceded by the address in the
file. Normally, lines should be terminated by a \n character;
but long lines will be broken up. Control characters in the
range 0x00 to 0x1f are rpinted as `^@' to `^_'. Bytes with the
high bit set are preceded by a tilde (~) and printed as if the
high bit were not set. The special characters (^,~,\) are
preceded by a backslash (\) to escape their special meaning.
As special cases, two values are represented numerically as
`\177' and `\377'. This flag will override all output format
specifiers except addresses.
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