-
- cksum,md5sum,sum - print file checksum and block count
-
- cksum [ 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.
- 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
- 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.
- 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) 2007-11-27
- author
- Glenn Fowler <gsf@research.att.com>
- author
- David Korn <dgk@research.att.com>
- copyright
- Copyright © 1992-2008 AT&T Intellectual Property
- license
- http://www.opensource.org/licenses/cpl1.0.txt