FEX-Emu/xxHash
1
0
Fork 0
mirror of https://github.com/FEX-Emu/xxHash.git synced 2024-11-23 22:49:39 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity
fa1368ad7a
xxHash/xxhsum.1.md
easyaspi314 (Devin) 9eb91a3b53 Let the Great Typo Hunt commence! 
Work in progress.

 - Fix many spelling/grammar issues, primarily in comments
 - Remove most spaces before punctuation
 - Update XXH3 comment
 - Wrap most comments to 80 columns
 - Unify most comments to use the same style
 - Use hexadecimal in the xxhash spec
 - Update help messages to better match POSIX/GNU conventions
 - Use HTML escapes in README.md to avoid UTF-8
 - Mark outdated benchmark/scores
2020-03-02 15:20:49 -05:00

3.7 KiB
Raw Blame History

xxhsum(1) -- 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 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 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.

OPTIONS

  • -V, --version: Displays xxhsum version and exits

  • -H: Hash selection. 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 : Read xxHash sums from 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.

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

  • -i: Only useful for benchmark mode (-b). See EXAMPLES for details. 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, thw 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)