sha1sum

compute and check SHA1 message digest

TLDR

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]

DESCRIPTION

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.

BUGS

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)

REPORTING BUGS

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

COPYRIGHT

Copyright © 2022 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.

AUTHOR

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