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Commands tagged md5sum from sorted by
Terminal - Commands tagged md5sum - 22 results
tar -cf - file1 dir1/ dir2/ | md5sum
2014-04-17 14:33:44
User: snipertyler
Functions: tar
-1

Doesn't create a file

Make sure to list the files / directories in the same order every time.

dd bs=1M if=/dev/scd0 of=./filename.iso OR readom -v dev='D:' f='./filename.iso' speed=2 retries=8
2013-10-23 15:53:27
User: scotharkins
Functions: dd
-1

This example is taken from Cygwin running on Win7Ent-64. Device names will vary by platform.

Both commands resulted in identical files per the output of md5sum, and ran in the same time down to the second (2m45s), less than 100ms apart. I timed the commands with 'time', which added before 'dd' or 'readom' gives execution times after the command completes. See 'man time' for more info...it can be found on any Unix or Linux newer than 1973. Yeah, that means everywhere.

readom is supposed to guarantee good reads, and does support flags for bypassing bad blocks where dd will either fail or hang.

readom's verbosity gave more interesting output than dd.

On Cygwin, my attempt with 'readom' from the first answer actually ended up reading my hard drive. Both attempts got to 5GB before I killed them, seeing as that is past any CD or standard DVD.

dd:

'bs=1M' says "read 1MB into RAM from source, then write that 1MB to output. I also tested 10MB, which shaved the time down to 2m42s.

'if=/dev/scd0' selects Cygwin's representation of the first CD-ROM drive.

'of=./filename.iso' simply means "create filename.iso in the current directory."

readom:

'-v' says "be a little noisy (verbose)." The man page implies more verbosity with more 'v's, e.g. -vvv.

dev='D:' in Cygwin explicitly specifies the D-drive. I tried other entries, like '/dev/scd0' and '2,0', but both read from my hard drive instead of the CD-ROM. I imagine my LUN-foo (2,0) was off for my system, but on Cygwin 'D:' sort of "cut to the chase" and did the job.

f='./filename.iso' specifies the output file.

speed=2 simply sets the speed at which the CD is read. I also tried 4, which ran the exact same 2m45s.

retries=8 simply means try reading a block up to 8 times before giving up. This is useful for damaged media (scratches, glue lines, etc.), allowing you to automatically "get everything that can be copied" so you at least have most of the data.

find . -type f -not -empty -printf "%-25s%p\n"|sort -n|uniq -D -w25|cut -b26-|xargs -d"\n" -n1 md5sum|sed "s/ /\x0/"|uniq -D -w32|awk -F"\0" 'BEGIN{l="";}{if(l!=$1||l==""){printf "\n%s\0",$1}printf "\0%s",$2;l=$1}END{printf "\n"}'|sed "/^$/d"
2013-10-22 13:34:19
User: alafrosty
Functions: awk cut find sed sort uniq xargs
0

* Find all file sizes and file names from the current directory down (replace "." with a target directory as needed).

* sort the file sizes in numeric order

* List only the duplicated file sizes

* drop the file sizes so there are simply a list of files (retain order)

* calculate md5sums on all of the files

* replace the first instance of two spaces (md5sum output) with a \0

* drop the unique md5sums so only duplicate files remain listed

* Use AWK to aggregate identical files on one line.

* Remove the blank line from the beginning (This was done more efficiently by putting another "IF" into the AWK command, but then the whole line exceeded the 255 char limit).

>>>> Each output line contains the md5sum and then all of the files that have that identical md5sum. All fields are \0 delimited. All records are \n delimited.

find ./ -type f -print0 | xargs -0 md5sum
md5sum filename | ncat hash.cymru.com 43
cat /var/lib/dpkg/info/*.md5sums|grep usr/sbin/sshd|sed 's,usr,/usr,'|md5sum -c
2013-03-12 11:20:48
User: Ztyx
Functions: cat grep md5sum sed
0

Replace "user/sbin/sshd" with the file you would like to check. If you are doing this due to intrusion, you obviously would want to check size, last modification date and md5 of the md5sum application itself. Also, note that "/var/lib/dpkg/info/*.md5sums" files might have been tampered with themselves. Neither to say, this is a useful command.

find-duplicates () { find "$@" -not -empty -type f -printf "%s\0" | sort -rnz | uniq -dz | xargs -0 -I{} -n1 find "$@" -type f -size {}c -print0 | xargs -0 md5sum | sort | uniq -w32 --all-repeated=separate; }
2013-01-23 23:20:26
User: mpeschke
Functions: find md5sum sort uniq xargs
-1

This is a modified version of the OP, wrapped into a bash function.

This version handles newlines and other whitespace correctly, the original has problems with the thankfully rare case of newlines in the file names.

It also allows checking an arbitrary number of directories against each other, which is nice when the directories that you think might have duplicates don't have a convenient common ancestor directory.

echo -n "password"|md5sum|awk '{print $1}'
2011-11-08 21:34:50
User: windfold
Functions: awk echo
3

This is mostly for my own notes but this command will compute a md5 message digest from the command line.

You can also replace md5sum with other checksum commands (e.g., sha1sum)

for i in $(find . -name *md5checksum_file* | sed 's/\(\.\/.*\)md5checksum_file.txt/\1/'); do cd "$i"; md5sum -c "md5checksum_file.txt"; cd -; done | tee ~/checksum_results.txt | grep -v "<current directory>"
2011-05-17 01:08:44
User: gocoogs
Functions: cd find grep md5sum sed tee
0

extracts path to each md5 checksum file, then, for each path, cd to it, check the md5sum, then cd - to toggle back to the starting directory. greps at the end to remove cd chattering on about the current directory.

awk '{command="echo "$2"|md5sum" ;command | getline $2; close(command);sub(/[[:blank:]].*/,"",$2); print $0}'
echo -n "String to MD5" | md5sum | sed -e 's/../& /g' -e 's/ -//'
echo -n "String to MD5" | md5sum | cut -b-32
echo -n "String to MD5" | md5sum | sed -e 's/[0-9a-f]\{2\}/& /g' -e 's/ -//'
2011-03-05 11:47:08
User: saibbot
Functions: echo md5sum sed
Tags: sed md5sum
1

Generates the md5 hash, without the trailing " -" and with the output "broken" into pairs of hexs.

echo -n "String to MD5" | md5sum | cut -f1 -d' '
2011-03-05 03:53:09
User: xakon
Functions: cut echo md5sum
-2

Nothing special about hashing here, only the use of cut, I think, could result at fewer keystrokes.

echo -n "String to get MD5" | md5sum | sed "s/ -//"
digest -a -v md5 <file-name>
md5sum <<<"test"
find . -type f -print0 | xargs -0 md5sum
find . -type f -exec md5sum {} \; > sum.md5
find -type d -name ".svn" -prune -o -not -empty -type f -printf "%s\n" | sort -rn | uniq -d | xargs -I{} -n1 find -type d -name ".svn" -prune -o -type f -size {}c -print0 | xargs -0 md5sum | sort | uniq -w32 --all-repeated=separate
2010-01-28 09:45:29
User: 2chg
Functions: find md5sum sort uniq xargs
2

Improvement of the command "Find Duplicate Files (based on size first, then MD5 hash)" when searching for duplicate files in a directory containing a subversion working copy. This way the (multiple dupicates) in the meta-information directories are ignored.

Can easily be adopted for other VCS as well. For CVS i.e. change ".svn" into ".csv":

find -type d -name ".csv" -prune -o -not -empty -type f -printf "%s\n" | sort -rn | uniq -d | xargs -I{} -n1 find -type d -name ".csv" -prune -o -type f -size {}c -print0 | xargs -0 md5sum | sort | uniq -w32 --all-repeated=separate
diff <(ssh server01 'cd config; find . -type f -exec md5sum {} \;| sort -k 2') <(ssh server02 'cd config;find . -type f -exec md5sum {} \;| sort -k 2')
2009-09-11 15:24:59
User: arcege
Functions: diff find md5sum sort ssh
13

This can be much faster than downloading one or both trees to a common servers and comparing the files there. After, only those files could be copied down for deeper comparison if needed.

echo "A great password" | md5sum
2009-04-24 14:32:56
User: ubersoldat
Functions: echo
-5

You can also use sha1sum and variants for longer passwords