Below is a summary of all of the options that GNU
Most options have two equivalent names, one of which is a single letter
-, and the other of which is a long name preceded by
--. Multiple single letter options (unless they take an
argument) can be combined into a single command line word:
- Print the differing bytes. Display control bytes as a
^ followed by a letter of the alphabet and precede bytes
that have the high bit set with
M- (which stands for "meta").
- Output a summary of usage and then exit.
- Ignore any differences in the first skip bytes of the input
files. Treat files with fewer than skip bytes as if they are
empty. If skip is of the form
from-skip:to-skip, skip the first from-skip
bytes of the first input file and the first to-skip bytes of the
- Print the (decimal) byte numbers and (octal) values of all differing bytes.
- Compare at most count input bytes.
- Do not print anything; only return an exit status indicating whether
the files differ.
- Output version information and then exit.
In the above table, operands that are byte counts are normally
decimal, but may be preceded by
0 for octal and
A byte count can be followed by a suffix to specify a multiple of that
count; in this case an omitted integer is understood to be 1. A bare
size letter, or one followed by
iB, specifies a multiple using
powers of 1024. A size letter followed by
B specifies powers
of 1000 instead. For example,
-n 4M and
-n 4MiB are
-n 4194304, whereas
-n 4MB is
-n 4000000. This notation is upward compatible
with the SI prefixes for decimal multiples and with the
IEC 60027-2 prefixes for binary multiples.
The following suffixes are defined. Large sizes like
1Y may be
rejected by your computer due to limitations of its arithmetic.
- kilobyte: 10^3 = 1000.
- kibibyte: 2^10 = 1024.
K is special: the SI prefix is
k and the IEC 60027-2 prefix is
Ki, but tradition and
k to mean
- megabyte: 10^6 = 1,000,000.
- mebibyte: 2^20 = 1,048,576.
- gigabyte: 10^9 = 1,000,000,000.
- gibibyte: 2^30 = 1,073,741,824.
- terabyte: 10^12 = 1,000,000,000,000.
- tebibyte: 2^40 = 1,099,511,627,776.
- petabyte: 10^15 = 1,000,000,000,000,000.
- pebibyte: 2^50 = 1,125,899,906,842,624.
- exabyte: 10^18 = 1,000,000,000,000,000,000.
- exbibyte: 2^60 = 1,152,921,504,606,846,976.
- zettabyte: 10^21 = 1,000,000,000,000,000,000,000
- 2^70 = 1,180,591,620,717,411,303,424.
Zi is a GNU extension to IEC 60027-2.)
- yottabyte: 10^24 = 1,000,000,000,000,000,000,000,000.
- 2^80 = 1,208,925,819,614,629,174,706,176.
Yi is a GNU extension to IEC 60027-2.)