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 file as binary file; xxhsum has 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
    Display 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
    Display help and exit

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

-c, --check
    Read xxHash sums from the FILEs and check them

q, --quiet
    Exit non-zero for improperly formatted checksum lines

--strict
    Don't print OK for each successfully verified file

--status
    Don't output anything, status code shows success

-w, --warn
    Warn about improperly formatted checksum lines

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.
First column means algorithm, second column is source data size in bytes, third column is number of hashes generated per second (throughput), and finally last column translates speed in mega-bytes per seconds.

    $ xxhsum -b -i10 -B16384

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

AUTHOR
Yann Collet

SEE ALSO
md5sum(1)