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>] ... xxhsum -b [<OPTION>] ...
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11       xxh32sum  is  equivalent to xxhsum -H0 xxh64sum is equivalent to xxhsum
12       -H1 xxh128sum is equivalent to xxhsum -H2
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DESCRIPTION

15       Print or check xxHash (32, 64 or 128 bits)  checksums.  When  no  FILE,
16       read  standard  input, except if it´s the console. When FILE is -, read
17       standard input even if it´s the console.
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19       xxhsum supports a command line syntax  similar  but  not  identical  to
20       md5sum(1). Differences are: xxhsum doesn´t have text/binary mode switch
21       (-b, -t); xxhsum always treats files as binary file; xxhsum has a  hash
22       bit width switch (-H);
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24       As xxHash is a fast non-cryptographic checksum algorithm, xxhsum should
25       not be used for security related purposes.
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27       xxhsum -b invokes benchmark mode. See OPTIONS and EXAMPLES for details.
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OPTIONS

30       -V, --version
31              Displays xxhsum version and exits
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33       -HHASHTYPE
34              Hash  selection.  HASHTYPE  means  0=XXH32,  1=XXH64,  2=XXH128,
35              3=XXH3.  Alternatively, HASHTYPE 32=XXH32, 64=XXH64, 128=XXH128.
36              Default value is 1 (64bits)
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38       --tag  Output in the BSD style.
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40       --little-endian
41              Set output hexadecimal checksum value as little  endian  conven‐
42              tion. By default, value is displayed as big endian.
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44       -h, --help
45              Displays help and exits
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47       The  following  four  options  are useful only when verifying checksums
48       (-c)
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50       -c, --check FILE
51              Read xxHash sums from FILE and check them
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53       -q, --quiet
54              Don´t print OK for each successfully verified file
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56       --strict
57              Return an error code if any line in the  file  is  invalid,  not
58              just if some checksums are wrong. This policy is disabled by de‐
59              fault, though UI will prompt an  informational  message  if  any
60              line in the file is detected invalid.
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62       --status
63              Don´t output anything. Status code shows success.
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65       -w, --warn
66              Emit  a warning message about each improperly formatted checksum
67              line.
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69       The following options are useful only benchmark purpose
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71       -b     Benchmark mode. See EXAMPLES for details.
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73       -b#    Specify ID of variant to be tested. Multiple variants can be se‐
74              lected, separated by a ´,´ comma.
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76       -BBLOCKSIZE
77              Only  useful  for benchmark mode (-b). See EXAMPLES for details.
78              BLOCKSIZE specifies benchmark mode´s test  data  block  size  in
79              bytes. Default value is 102400
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81       -iITERATIONS
82              Only  useful  for benchmark mode (-b). See EXAMPLES for details.
83              ITERATIONS specifies number of iterations in  benchmark.  Single
84              iteration  lasts  approximately 1000 milliseconds. Default value
85              is 3
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EXIT STATUS

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

92       Output  xxHash  (64bit)  checksum  values of specific files to standard
93       output
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96           $ xxhsum -H1 foo bar baz
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100       Output xxHash (32bit and 64bit) checksum values of  specific  files  to
101       standard output, and redirect it to xyz.xxh32 and qux.xxh64
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104           $ xxhsum -H0 foo bar baz > xyz.xxh32
105           $ xxhsum -H1 foo bar baz > qux.xxh64
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109       Read xxHash sums from specific files and check them
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112           $ xxhsum -c xyz.xxh32 qux.xxh64
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116       Benchmark  xxHash  algorithm. By default, xxhsum benchmarks xxHash main
117       variants on a synthetic sample of 100 KB, and print results into  stan‐
118       dard  output.  The  first column is the algorithm, the second column is
119       the source data size in bytes, the third column is the number of hashes
120       generated  per  second (throughput), and finally the last column trans‐
121       lates speed in megabytes per second.
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124           $ xxhsum -b
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128       In the following example, the sample to hash is set to 16384 bytes, the
129       variants  to  be  benched are selected by their IDs, and each benchmark
130       test is repeated 10 times, for increased accuracy.
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133           $ xxhsum -b1,2,3 -i10 -B16384
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BUGS

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

141       Yann Collet
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