-
- cksum,md5sum,sum - print file checksum and block count
-
- cksum,md5sum,sum [ options ] [ file ... ]
-
- sum lists the checksum, and for most methods the block count, for each file argument. The standard input is
read if there are no file arguments. getconf UNIVERSE determines the default sum method: att
for the att universe, bsd otherwise. The default for the other commands is the command name itself. The
att method is a true sum, all others are order dependent.
- Method names consist of a leading identifier and 0 or more options separated by -.
- getconf PATH_RESOLVE determines how symbolic links are handled. This can be explicitly overridden by the --logical
, --metaphysical, and --physical options below. PATH_RESOLVE can be one of:
- logical
- Follow all symbolic links.
- metaphysical
- Follow command argument symbolic links, otherwise don't follow.
- physical
- Don't follow symbolic links.
-
- -a, --all
- List the checksum for all files. Use with --total to list both individual and
total checksums and block counts.
- -b, --binary
- Read files in binary mode. This is the default.
- -B, --scale=scale
- Block count scale (bytes per block) override for methods that include
size in the output. The default is method specific.
- -c, --check
- Each file is interpreted as the output from a previous sum. If --header
or --permissions was specified in the previous sum then the checksum method is automatically
determined, otherwise --method must be specified. The listed checksum is compared with the current value and a
warning is issued for each file that does not match. If file was generated by --permissions then the file
mode, user and group are also checked. Empty lines, lines starting with #<space>, or the line # are
ignored. Lines containing no blanks are interpreted as [no]name[=value] options:
- method=name
- Checksum method to apply to subsequent lines.
- permissions
- Subsequent lines were generated with --permissions.
- -h, --header
- Print the checksum method as the first output line. Used with --check and --permissions
.
- -l, --list
- Each file is interpreted as a list of files, one per line, that is checksummed.
- -p, --permissions
- If --check is not specified then list the file mode, user and group
between the checksum and path. User and group matching the caller are output as -. If --check is
specified then the mode, user and group for each path in file are updated if necessary to match those in file
. A warning is printed on the standard error for each changed file.
- -R, --recursive
- Recursively checksum the contents of directories.
- -S, --silent|status
- No output for --check; 0 exit status means all sums matched, non-0
means at least one sum failed to match. Ignored for --permissions.
- -t, --total
- List only the total checksum and block count of all files. --all --total
lists each checksum and the total. The total checksum and block count may be different from the checksum and block
count of the catenation of all files due to partial blocks that may occur when the files are treated separately.
- -T, --text
- Read files in text mode (i.e., treat \r\n as \n).
- -w, --warn
- Warn about invalid --check lines. On by default; -w means --nowarn.
- -x, --method|algorithm=method
- Specifies the checksum method to apply. Parenthesized
method options are readonly implementation details.
- att|sys5|s5|default
- The system 5 release 4 checksum. This is the
default for sum when getconf UNIVERSE is att. This is the only true sum; all of the other methods
are order dependent.
- ast4|32x4|tw
- The ast 128 bit PRNG hash generated by catenating 4
separate 32 bit PNRG hashes. The block count is not printed.
- bsd|ucb
- The BSD checksum.
- crc
- 32 bit CRC (cyclic redundancy check).
- polynomial=mask
- The 32 bit crc polynomial bitmask with implicit bit
32. The default value is 0xedb88320.
- done[=number]
- XOR the final crc value with number. 0xffffffff
is used if number is omitted. The option value may be omitted. The default value is 0.
- init[=number]
- The initial crc value. 0xffffffff is used if number
is omitted. The option value may be omitted. The default value is 0.
- rotate
- XOR each input character with the high order crc byte (instead of the low
order).
- size[=number]
- Include the total number of bytes in the crc. number
, if specified, is first XOR'd into the size. The option value may be omitted. The default value is 0.
- prng
- 32 bit PRNG (pseudo random number generator) hash.
- mpy=number
- The 32 bit PRNG multiplier. The default value is 0x01000193
.
- add=number
- The 32 bit PRNG addend. The default value is 0.
- init[=number]
- The PRNG initial value. 0xffffffff is used if number
is omitted. The option value may be omitted. The default value is 0x811c9dc5.
- md5|MD5
- The RSA Data Security, Inc. MD5 Message-Digest Method, 1991-2, used with
permission. The block count is not printed.
- (version)
- md5 (RSA Data Security, Inc. MD5 Message-Digest, 1991-2) 1996-02-29
- sha1|SHA1|sha-1|SHA-1
- FIPS 180-1 SHA-1 secure hash algorithm 1.
- (version)
- sha1 (FIPS 180-1) 1996-09-26
- (author)
- Steve Reid <steve@edmweb.com>
- sha256|sha-256|SHA256|SHA-256
- FIPS SHA-256 secure hash
algorithm.
- (version)
- sha-256 (FIPS) 2000-01-01
- (author)
- Aaron D. Gifford
- sha384|sha-384|SHA384|SHA-384
- FIPS SHA-384 secure hash
algorithm.
- (version)
- sha-384 (FIPS) 2000-01-01
- (author)
- Aaron D. Gifford
- sha512|sha-512|SHA512|SHA-512
- FIPS SHA-512 secure hash
algorithm.
- (version)
- sha-512 (FIPS) 2000-01-01
- (author)
- Aaron D. Gifford
- posix|cksum|std|standard
- The posix 1003.2-1992 32 bit crc
checksum. This is the default cksum(1) method. Shorthand for crc-0x04c11db7-rotate-done-size
.
- zip
- The zip(1) crc. Shorthand for crc-0xedb88320-init-done
.
- fddi
- The FDDI crc. Shorthand for crc-0xedb88320-size=0xcc55cc55.
- fnv|fnv1
- The Fowler-Noll-Vo 32 bit PRNG hash with non-zero initializer (FNV-1).
Shorthand for prng-0x01000193-init=0x811c9dc5.
- ast|strsum
- The ast strsum(3)
PRNG hash. Shorthand for prng-0x63c63cd9-add=0x9c39c33d.
- -L, --logical|follow
- Follow symbolic links when traversing directories. The default is determined
by getconf PATH_RESOLVE.
- -H, --metaphysical
- Follow command argument symbolic links, otherwise don't follow symbolic links
when traversing directories. The default is determined by getconf PATH_RESOLVE.
- -P, --physical
- Don't follow symbolic links when traversing directories. The default is determined
by getconf PATH_RESOLVE.
- -r, --bsd
- Equivalent to --method=bsd --scale=512 for compatibility with other sum(1)
implementations.
- -s, --sysv
- Equivalent to --method=sys5 for compatibility with other sum(1)
implementations.
-
- getconf(1), tw(1),
uuencode(1)
-
- version
- sum (AT&T Research) 2009-11-28
- author
- Glenn Fowler <gsf@research.att.com
>
- author
- David Korn <dgk@research.att.com>
- copyright
- Copyright © 1992-2010 AT&T Intellectual Property
- license
- http://www.opensource.org/licenses/cpl1.0.txt