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b2sum - compute and check BLAKE2 message digest

B2SUM(1) User Commands B2SUM(1)


b2sum - compute and check BLAKE2 message digest


b2sum [ OPTION]... [FILE]...


Print or check BLAKE2 (512-bit) checksums.
With no FILE, or when FILE is -, read standard input.
-b, --binary
read in binary mode
-c, --check
read BLAKE2 sums from the FILEs and check them
-l, --length
digest length in bits; must not exceed the maximum for the blake2 algorithm and must be a multiple of 8
create a BSD-style checksum
-t, --text
read in text mode (default)

The following five options are useful only when verifying checksums:

don't fail or report status for missing files
don't print OK for each successfully verified file
don't output anything, status code shows success
exit non-zero for improperly formatted checksum lines
-w, --warn
warn about improperly formatted checksum lines
display this help and exit
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.


Written by Padraig Brady and Samuel Neves.


GNU coreutils online help: <>
Report b2sum translation bugs to <> Copyright © 2017 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.


Full documentation at: <>
or available locally via: info '(coreutils) b2sum invocation'
October 2017 GNU coreutils 8.28