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
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DESCRIPTION

16       Print  or  check  xxHash  (32 or 64bit) checksums. When FILE is -, read
17       standard input.
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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 file as binary file; xxhsum has hash bit
22       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              Display xxhsum version
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33       -HHASHTYPE
34              Hash selection. HASHTYPE means 0=32bits, 1=64bits. Default value
35              is 1 (64bits)
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37       --little-endian
38              Set  output  hexadecimal checksum value as little endian conven‐
39              tion. By default, value is displayed as big endian.
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41       -h, --help
42              Display help and exit
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44       The following four options are useful  only  when  verifying  checksums
45       (-c)
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47       -c, --check
48              Read xxHash sums from the FILEs and check them
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50       --quiet
51              Exit non-zero for improperly formatted checksum lines
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53       --strict
54              Don´t print OK for each successfully verified file
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56       --status
57              Don´t output anything, status code shows success
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59       -w, --warn
60              Warn about improperly formatted checksum lines
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62       The following options are useful only benchmark purpose
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64       -b     Benchmark mode. See EXAMPLES for details.
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66       -BBLOCKSIZE
67              Only  useful  for benchmark mode (-b). See EXAMPLES for details.
68              BLOCKSIZE specifies benchmark mode´s test  data  block  size  in
69              bytes. Default value is 102400
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71       -iITERATIONS
72              Only  useful  for benchmark mode (-b). See EXAMPLES for details.
73              ITERATIONS specifies number of iterations in  benchmark.  Single
74              iteration takes at least 2500 milliseconds. Default value is 3
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EXIT STATUS

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

81       Output xxHash (64bit) checksum values of  specific  files  to  standard
82       output
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86           $ xxhsum -H1 foo bar baz
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90       Output  xxHash  (32bit  and 64bit) checksum values of specific files to
91       standard output, and redirect it to xyz.xxh32 and qux.xxh64
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95           $ xxhsum -H0 foo bar baz > xyz.xxh32
96           $ xxhsum -H1 foo bar baz > qux.xxh64
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100       Read xxHash sums from specific files and check them
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104           $ xxhsum -c xyz.xxh32 qux.xxh64
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108       Benchmark xxHash algorithm for 16384 bytes data  in  10  times.  xxhsum
109       benchmarks xxHash algorithm for 32-bit and 64-bit and output results to
110       standard output. First column means algorithm, second column is  source
111       data  size  in  bytes,  last  column  means  hash  generation  speed in
112       mega-bytes per seconds.
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116           $ xxhsum -b -i10 -B16384
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BUGS

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

124       Yann Collet
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