- Calculate the SHA1 checksum for a file:
- Calculate SHA1 checksums for multiple files:
sha1sum filename1 filename2
- Calculate and save the list of SHA1 checksums to a file:
sha1sum filename1 filename2 > filename.sha1
- Read a file of SHA1 sums and verify all files have matching checksums:
sha1sum --check filename.sha1
- Only show a message for files for which verification fails:
sha1sum --check --quiet filename.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 SHA1 sums from the FILEs and check them
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
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 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)
Written by Ulrich Drepper, Scott Miller, and David Madore.
GNU coreutils online help: <https://www.gnu.org/software/coreutils/>
Report any translation bugs to <https://translationproject.org/team/>
Copyright © 2020 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.
Full documentation <https://www.gnu.org/software/coreutils/sha1sum>
or available locally via: info '(coreutils) sha1sum invocation'
cksfv(1), debsign(1), guestfish(1), guestfs(3), monit(1), perl5140delta(1), rdfind(1).