hd(1XNX) (XENIX System Compatibility) hd(1XNX)
NAME
hd - (XENIX) display files in a specified format
SYNOPSIS
hd [-[abwl][xdo][cA][t]] [-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 specifiers set: -abA.
This says that addresses (file offsets) and bytes are printed
in hexadecimal and that only ASCII characters are also
printed. If no file argument is given, the standard input is
read.
Options
Format specifiers, described below, may specify addresses,
bytes, words (2 bytes), or longs (4 bytes). Output specifiers
determine whether to print only the ASCII-readable characters,
or to print all printable characters, special C escapes as
defined in the language, and remaining values in the specified
base. Base specifiers determine whether the data is to be
printed in hexadecimal, decimal, or octal. A special flag
directs output to a test file, with each line preceded by the
address in the file.
Format and base specifiers may be freely combined and repeated
as desired in order to specify different bases (hexadecimal,
decimal, and/or octal) for different formats (addresses,
bytes, and so on). All format specifiers appearing in a
single argument are applied as appropriate to all other flags
in that argument.
If no format specifier is given, -abwlc is used as the
default. If no other output format (other than addresses, a)
is given, bx is assumed (byte, in hexadecimal).
Format specifiers are used as follows:
-abwl Format type specifier for address, bytes, words, and
longs, respectively. Only one base specifier (described
below) is used for addresses; the address appears on the
first line of output that begins each new offset in the
input.
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hd(1XNX) (XENIX System Compatibility) hd(1XNX)
cA These are the output specifiers, and should be entered
directly to the right of one or more of the format type
specifiers (that is, a, b, w, or l). If only one output
specifier appears on the command line, it is assumed to
apply to all the format type specifiers.
The character format flag, c, directs hd to print
printable characters unchanged, special C escapes as
defined in the language, and remaining values in the
specified base.
The ASCII format flag, A, directs hd to print all
printable characters unchanged, and all others as a
period (.).
xdo The base specifiers denote hexadecimal, decimal and
octal. If no base specifier is given, the default is
xdo, meaning present the output in all three formats,
hexadecimal, decimal, and octal.
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.
Following are the remaining options for hd:
-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
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hd(1XNX) (XENIX System Compatibility) hd(1XNX)
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.
Copyright 1994 Novell, Inc. Page 3