XXHSUM(1)

NAME
xxhsum - print or check xxHash non-cryptographic checksums

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

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

DESCRIPTION
Print or check xxHash (32, 64 or 128 bits) checksums. When FILE is -, read standard input.

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 files; 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.

OPTIONS

-V, --version
    Displays xxhsum version and exits

-HHASHTYPE
    Hash selection. HASHTYPE means 0=32bits, 1=64bits, 2=128bits. Default value is 1 (64bits)

-q, --quiet
    Remove status messages like "Loading..." written to stderr .

--little-endian
    Set output hexadecimal checksum value as little endian convention. By default, value is displayed as big endian.

-h, --help
    Displays help and exits

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

-c, --check FILE
    Read xxHash sums from FILE and check them

-q, --quiet
    On top of removing status messages written to stderr, also don't print OK for each successfully verified file

--strict
    Return an error code if any line in the file is invalid, not just if some checksums are wrong. This policy is disabled by default, though UI will prompt an informational message if any line in the file is detected invalid.

--status
    Don't output anything. Status code shows success.

-w, --warn
    Emit a warning message about each improperly formatted checksum line.

The following options are useful only benchmark purpose

-b  Benchmark mode. See EXAMPLES for details.

-BBLOCKSIZE
    Only useful for benchmark mode (-b). See EXAMPLES for details. BLOCKSIZE specifies benchmark mode's test data block size in bytes. Default value is 102400

-iITERATIONS
    Only useful for benchmark mode (-b). See EXAMPLES for details. ITERATIONS specifies number of iterations in benchmark. Single iteration lasts approximately 1000 milliseconds. Default value is 3

EXIT STATUS
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.

EXAMPLES
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 for 16384 bytes data in 10 times. xxhsum benchmarks all xxHash variants and output results to 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 -i10 -B16384

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

AUTHOR
Yann Collet

SEE ALSO
md5sum(1)