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b3sum - Man Page

manual page for b3sum 1.5.1

Examples (TL;DR)


b3sum [Options] [FILE]...




Files to hash, or checkfiles to check

When no file is given, or when - is given, read standard input.


Use the keyed mode, reading the 32-byte key from stdin
--derive-key <CONTEXT>
Use the key derivation mode, with the given context string

Cannot be used with --keyed.

-l,  --length <LEN>
The number of output bytes, before hex encoding

[default: 32]

--seek <SEEK>
The starting output byte offset, before hex encoding

[default: 0]

--num-threads <NUM>
The maximum number of threads to use

By default, this is the number of logical cores. If this flag is omitted, or if its value is 0, RAYON_NUM_THREADS is also respected.

Disable memory mapping

Currently this also disables multithreading.

Omit filenames in the output
Write raw output bytes to stdout, rather than hex
--no-names is implied. In this case, only a single input is allowed.
-c,  --check
Read BLAKE3 sums from the [FILE]s and check them
Skip printing OK for each checked file

Must be used with --check.

-h,  --help
Print help (see a summary with '-h')
-V,  --version
Print version


May 2024 b3sum 1.5.1