b2sum - Man Page
compute and check BLAKE2 message digest
Examples (TL;DR)
- Calculate the BLAKE2 checksum for one or more files:
b2sum path/to/file1 path/to/file2 ...
- Calculate and save the list of BLAKE2 checksums to a file:
b2sum path/to/file1 path/to/file2 ... > path/to/file.b2
- Calculate a BLAKE2 checksum from
stdin
:command | b2sum
- Read a file of BLAKE2 sums and filenames and verify all files have matching checksums:
b2sum --check path/to/file.b2
- Only show a message for missing files or when verification fails:
b2sum --check --quiet path/to/file.b2
- Only show a message when verification fails, ignoring missing files:
b2sum --ignore-missing --check --quiet path/to/file.b2
Synopsis
b2sum [OPTION]... [FILE]...
Description
Print or check BLAKE2b (512-bit) checksums.
With no FILE, or when FILE is -, read standard input.
Mandatory arguments to long options are mandatory for short options too.
- -b, --binary
read in binary mode
- -c, --check
read checksums from the FILEs and check them
- -l, --length=BITS
digest length in bits; must not exceed the max for the blake2 algorithm and must be a multiple of 8
- --tag
create a BSD-style checksum
- -t, --text
read in text mode (default)
- -z, --zero
end each output line with NUL, not newline, and disable file name escaping
The following five options are useful only when verifying checksums
- --ignore-missing
don't fail or report status for missing files
- --quiet
don't print OK for each successfully verified file
- --status
don't output anything, status code shows success
- --strict
exit non-zero for improperly formatted checksum lines
- -w, --warn
warn about improperly formatted checksum lines
- --help
display this help and exit
- --version
output version information and exit
The sums are computed as described in RFC 7693. When checking, the input should be a former output of this program. The default mode is to print a line with: checksum, a space, a character indicating input mode ('*' for binary, ' ' for text or where binary is insignificant), and name for each FILE.
Note: There is no difference between binary mode and text mode on GNU systems.
Author
Written by Padraig Brady and Samuel Neves.
Reporting Bugs
GNU coreutils online help: <https://www.gnu.org/software/coreutils/>
Report any translation bugs to <https://translationproject.org/team/>
Copyright
Copyright © 2023 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
See Also
Full documentation <https://www.gnu.org/software/coreutils/b2sum>
or available locally via: info '(coreutils) b2sum invocation'