Commands by masterofdisaster (5)

  • When you have different digital cameras, different people, friends and you want to merge all those pictures together, then you get files with same names or files with 3 and 4 digit numbers etc. The result is a mess if you copy it together into one directory. But if you can add an offset to the picture number and set the number of leading zeros in the file name's number then you can manage. OFFS != 0 and LZ the same as the files currently have is not supported. Or left as an exercise, hoho ;) I love NF="${NF/#+(0)/}",it looks like a magic bash spell.


    2
    OFFS=30;LZ=6;FF=$(printf %%0%dd $LZ);for F in *.jpg;do NF="${F%.jpg}";NF="${NF/#+(0)/}";NF=$[NF+OFFS];NF="$(printf $FF $NF)".jpg;if [ "$F" != "$NF" ];then mv -iv "$F" "$NF";fi;done
    masterofdisaster · 2010-11-08 22:48:56 2
  • Nice reading in the morning on the way to work, but sadly the .tar.gz for the whole issue 66 is not on phrack's website yet. So use wget to download.


    2
    mkdir phrack66; (cd phrack66; for n in {1..17} ; do echo "http://www.phrack.org/issues.html?issue=66&id=$n&mode=txt" ; done | xargs wget)
    masterofdisaster · 2009-06-11 21:42:42 1
  • What do you do when nmap is not available and you want to see the hosts responding to an icmp echo request ? This one-liner will print all hosts responding with their ipv4 address.


    3
    ( nw=192.168.0 ; h=1; while [ $h -lt 255 ] ; do ( ping -c2 -i 0.2 -W 0.5 -n $nw.$h & ); h=$[ $h + 1 ] ; done ) | awk '/^64 bytes.*/ { gsub( ":","" ); print $4 }' | sort -u
    masterofdisaster · 2009-06-07 15:14:46 0
  • Sort ls output of all files in current directory in ascending order Just the 20 biggest ones: ls -la | sort -k 5bn | tail -n 20 A variant for the current directory tree with subdirectories and pretty columns is: find . -type f -print0 | xargs -0 ls -la | sort -k 5bn | column -t And finding the subdirectories consuming the most space with displayed block size 1k: du -sk ./* | sort -k 1bn | column -t


    6
    ls -la | sort -k 5bn
    masterofdisaster · 2009-06-07 14:35:17 3
  • This one-liner will the *delete* without any further confirmation all 100% duplicates but one based on their md5 hash in the current directory tree (i.e including files in its subdirectories). Good for cleaning up collections of mp3 files or pictures of your dog|cat|kids|wife being present in gazillion incarnations on hd. md5sum can be substituted with sha1sum without problems. The actual filename is not taken into account-just the hash is used. Whatever sort thinks is the first filename is kept. It is assumed that the filename does not contain 0x00. As per the good suggestion in the first comment, this one does a hard link instead: find . -xdev -type f -print0 | xargs -0 md5sum | sort | perl -ne 'chomp; $ph=$h; ($h,$f)=split(/\s+/,$_,2); if ($h ne $ph) { $k = $f; } else { unlink($f); link($k, $f); }' Show Sample Output


    19
    find . -type f -print0|xargs -0 md5sum|sort|perl -ne 'chomp;$ph=$h;($h,$f)=split(/\s+/,$_,2);print "$f"."\x00" if ($h eq $ph)'|xargs -0 rm -v --
    masterofdisaster · 2009-06-07 03:14:06 2

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

find co-ordinates of a location
Just add this to your .bashrc file. Use quotes when query has multiple word length.

Create the authorization header required for a Twitter stream feed
This is the FOURTH in a set of five commands. Please see my other commands for the previous three steps. This command builds the authorization header required by Twitter. For this command to work, see my previous 3 commands (step1, step2 and step3) as they are required to build the environment variables used in this command. For more information on the authorization header, go to dev.twitter.com/apps, click on any of your apps (or create a new one) and then click on the "OAuth Tool" tab.

Compute the average number of KB per file for each dir
Shorter version using --tag

I finally found out how to use notify-send with at or cron
You can write a script that does this : $remind []

Look for English words in /dev/urandom
Little faster alternative.

Display any tcp connections to apache
Sometimes apache will get stuck in an established state where you can't get a list of the connecting IP's from mod_status... not a good thing when you need to ban an abusive ip.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Get full directory path of a script regardless of where it is run from
Also resolves symlinks, showing the full path of the link target

list block devices
Shows all block devices in a tree with descruptions of what they are.

Show a passive popup in KDE
Display a passive popup during seconds. Additionnaly, --title can be used to set the title of the popup. This is a nice way to communicate with a desktop user of a machine you have an SSH access on : DISPLAY=:0 sudo -u $user -H kdialog --passivepopup "Hello you" 10 --title "cli IM"


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: