xxhsum(1)

1XXHSUM(1)                        User Commands                       XXHSUM(1)
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NAME

6       xxhsum - print or check xxHash non-cryptographic checksums
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SYNOPSIS

9       xxhsum [<OPTION>] ... [<FILE>] ...
10       xxhsum -b [<OPTION>] ...
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12       xxh32sum is equivalent to xxhsum -H0
13       xxh64sum is equivalent to xxhsum -H1
14       xxh128sum is equivalent to xxhsum -H2
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DESCRIPTION

17       Print  or  check xxHash (32, 64 or 128 bits) checksums. When FILE is -,
18       read standard input.
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20       xxhsum supports a command line syntax  similar  but  not  identical  to
21       md5sum(1). Differences are: xxhsum doesn´t have text/binary mode switch
22       (-b, -t); xxhsum always treats file as binary file; xxhsum has hash bit
23       width switch (-H);
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25       As xxHash is a fast non-cryptographic checksum algorithm, xxhsum should
26       not be used for security related purposes.
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28       xxhsum -b invokes benchmark mode. See OPTIONS and EXAMPLES for details.
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OPTIONS

31       -V, --version
32              Display xxhsum version and exits
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34       -HHASHTYPE
35              Hash selection. HASHTYPE means  0=32bits,  1=64bits,  2=128bits.
36              Default value is 1 (64bits)
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38       -q, --quiet
39              Remove status messages like "Loading ..." written to stderr .
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41       --little-endian
42              Set  output  hexadecimal checksum value as little endian conven‐
43              tion. By default, value is displayed as big endian.
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45       -h, --help
46              Display help and exit
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48       The following four options are useful  only  when  verifying  checksums
49       (-c)
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51       -c, --check
52              Read xxHash sums from the FILEs and check them
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54       q, --quiet
55              Exit non-zero for improperly formatted checksum lines
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57       --strict
58              Don´t print OK for each successfully verified file
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60       --status
61              Don´t output anything, status code shows success
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63       -w, --warn
64              Warn about improperly formatted checksum lines
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66       The following options are useful only benchmark purpose
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68       -b     Benchmark mode. See EXAMPLES for details.
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70       -BBLOCKSIZE
71              Only  useful  for benchmark mode (-b). See EXAMPLES for details.
72              BLOCKSIZE specifies benchmark mode´s test  data  block  size  in
73              bytes. Default value is 102400
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75       -iITERATIONS
76              Only  useful  for benchmark mode (-b). See EXAMPLES for details.
77              ITERATIONS specifies number of iterations in  benchmark.  Single
78              iteration  lasts  approximately 1000 milliseconds. Default value
79              is 3
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EXIT STATUS

82       xxhsum exit 0 on success, 1 if at least one file couldn´t  be  read  or
83       doesn´t have the same checksum as the -c option.
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EXAMPLES

86       Output  xxHash  (64bit)  checksum  values of specific files to standard
87       output
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91           $ xxhsum -H1 foo bar baz
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95       Output xxHash (32bit and 64bit) checksum values of  specific  files  to
96       standard output, and redirect it to xyz.xxh32 and qux.xxh64
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100           $ xxhsum -H0 foo bar baz > xyz.xxh32
101           $ xxhsum -H1 foo bar baz > qux.xxh64
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105       Read xxHash sums from specific files and check them
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109           $ xxhsum -c xyz.xxh32 qux.xxh64
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113       Benchmark  xxHash  algorithm  for  16384 bytes data in 10 times. xxhsum
114       benchmarks all xxHash variants and output results to standard output.
115       First column means algorithm, second column  is  source  data  size  in
116       bytes,  third column is number of hashes generated per second (through‐
117       put), and finally last column translates speed in mega-bytes  per  sec‐
118       onds.
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122           $ xxhsum -b -i10 -B16384
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BUGS

127       Report bugs at: https://github.com/Cyan4973/xxHash/issues/
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AUTHOR

130       Yann Collet
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