"Fossies" - the Fresh Open Source Software Archive

Member "xxHash-0.8.0/xxhsum.1.md" (27 Jul 2020, 4156 Bytes) of package /linux/misc/xxHash-0.8.0.tar.gz:

As a special service "Fossies" has tried to format the requested source page into HTML format (assuming markdown format). Alternatively you can here view or download the uninterpreted source code file. A member file download can also be achieved by clicking within a package contents listing on the according byte size field. See also the latest Fossies "Diffs" side-by-side code changes report for "xxhsum.1.md": 0.7.4_vs_0.8.0.

xxhsum(1) -- print or check xxHash non-cryptographic checksums


xxhsum [<OPTION>] ... [<FILE>] ... xxhsum -b [<OPTION>] ...

xxh32sum is equivalent to xxhsum -H0 xxh64sum is equivalent to xxhsum -H1 xxh128sum is equivalent to xxhsum -H2


Print or check xxHash (32, 64 or 128 bits) checksums. When no , read standard input, except if it's the console. When is -, read standard input even if it's the console.

xxhsum supports a command line syntax similar but not identical to md5sum(1). Differences are: xxhsum doesn't have text/binary mode switch (-b, -t); xxhsum always treats files as binary file; xxhsum has a hash bit width switch (-H);

As xxHash is a fast non-cryptographic checksum algorithm, xxhsum should not be used for security related purposes.

xxhsum -b invokes benchmark mode. See OPTIONS and EXAMPLES for details.


The following four options are useful only when verifying checksums (-c)

The following options are useful only benchmark purpose


xxhsum exit 0 on success, 1 if at least one file couldn't be read or doesn't have the same checksum as the -c option.


Output xxHash (64bit) checksum values of specific files to standard output

$ xxhsum -H1 foo bar baz

Output xxHash (32bit and 64bit) checksum values of specific files to standard output, and redirect it to xyz.xxh32 and qux.xxh64

$ xxhsum -H0 foo bar baz > xyz.xxh32
$ xxhsum -H1 foo bar baz > qux.xxh64

Read xxHash sums from specific files and check them

$ xxhsum -c xyz.xxh32 qux.xxh64

Benchmark xxHash algorithm. By default, xxhsum benchmarks xxHash main variants on a synthetic sample of 100 KB, and print results into standard output. The first column is the algorithm, the second column is the source data size in bytes, the third column is the number of hashes generated per second (throughput), and finally the last column translates speed in megabytes per second.

$ xxhsum -b

In the following example, the sample to hash is set to 16384 bytes, the variants to be benched are selected by their IDs, and each benchmark test is repeated 10 times, for increased accuracy.

$ xxhsum -b1,2,3 -i10 -B16384


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


Yann Collet