sha1sum

Calculate the SHA1 checksum for a file

$ sha1sum [path/to/file]

Calculate SHA1 checksums for multiple files

$ sha1sum [path/to/file1] [path/to/file2]

Calculate and save the list of SHA1 checksums to a file

$ sha1sum [path/to/file1] [path/to/file2] > [path/to/file.sha1]

Read a file of SHA1 sums and verify all files have matching checksums

$ sha1sum --check [path/to/file.sha1]

Only show a message for missing files or when verification fails

$ sha1sum --check --quiet [path/to/file.sha1]

Only show a message for files for which verification fails, ignoring missing files

$ sha1sum --ignore-missing --check --quiet [path/to/file.sha1]

sha1sum [OPTION]... [FILE]...

Print or check SHA1 (160-bit) checksums.

With no FILE, or when FILE is -, read standard input.

-b, --binary

read in binary mode

-c, --check

read checksums from the FILEs and check them

--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 FIPS-180-1. 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.

Do not use the SHA-1 algorithm for security related purposes. Instead, use an SHA-2 algorithm, implemented in the programs sha224sum(1), sha256sum(1), sha384sum(1), sha512sum(1), or the BLAKE2 algorithm, implemented in b2sum(1)

GNU coreutils online help: <https://www.gnu.org/software/coreutils/>
Report any translation bugs to <https://translationproject.org/team/>

Copyright © 2021 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.

cksum(1) Full documentation <https://www.gnu.org/software/coreutils/sha1sum> or available locally via: info '(coreutils) sha1sum invocation'

Written by Ulrich Drepper, Scott Miller, and David Madore.