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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.
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:
just a leaner, smaller version. Love the original idea!
Sorts blank line delimited paragraphs. '-i' -- case insensitivity option -- removes redundant paragraphs in a case insensitive way, and then sorts in a case insensitive way.
If you search CommandLineFu with multiple anded terms searches, redundancy can ensue. This sorts the retrieved text (among other kinds of data), and removes the redundancy.
Often you want to nmap a list of IPs using the -iL flag. This is an easy way to generate a list of IPs that are online in a specific subnet or IP range (192.168.1.100-110).
Useful when specifying char encoding for Python and/or your editor
Very usefull script to use when uoy must print all files from a directory.
Strips the audio track from a webm video. Use this in combination with clive or youtube-dl.
This will show where your Perl installation is looking for modules.
Fully recharge your computer battery and start this script.
It will create or clean the file named battery.txt, print a start on it and every minute it will append a time stamp to it.
Batteries last few hours, and each hour will have 60 lines of time stamping. Really good for assuring the system was tested in real life with no surprises.
The last time stamp inside the battery.txt file is of interest. It is the time the computer went off, as the battery was dead!
Turn on your computer after that, on AC power of course, and open battery.txt. Read the first and last time stamps and now you really know if you can trust your computer sensors.
If you want a simple line of text inside the battery.txt file, use this:
watch -n 60 'date > battery.txt'
The time of death will be printed inside
Using -f treats the process name as a pattern so you don't have to include the full path in the command. Thus 'pkill -f firefox' works, even with iceweasel.
shell function which allows you to tag files by creating symbolic links directories in a 'tags' folder.
The tag function takes a tag name as its first argument, then a list of files which take that tag. The directory $HOME/tags/tagname will then hold symbolic links to each of the tagged files. This function was modified from bartonski's (http://www.commandlinefu.com/commands/view/10216) inspired by tmsu (found at https://bitbucket.org/oniony/tmsu/wiki/Home) with readlink function by flxndn (http://www.commandlinefu.com/commands/view/10222).
tag dog airedale.txt .shizturc weimeraner.pl
This will create $HOME/tags/dog which contains symbolic links to airedale.txt .shizturc and weimeraner.pl
The lastb command presents you with the history of failed login attempts (stored in /var/log/btmp). The reference file is read/write by root only by default. This can be quite an exhaustive list with lots of bots hammering away at your machine. Sometimes it is more important to see the scale of things, or in this case the volume of failed logins tied to each source IP.
The awk statement determines if the 3rd element is an IP address, and if so increments the running count of failed login attempts associated with it. When done it prints the IP and count.
The sort statement sorts numerically (-n) by column 3 (-k 3), so you can see the most aggressive sources of login attempts. Note that the ':' character is the 2nd column, and that the -n and -k can be combined to -nk.
Please be aware that the btmp file will contain every instance of a failed login unless explicitly rolled over. It should be safe to delete/archive this file after you've processed it.
Resets a scrambled terminal into its orignal state.
The command `cat file >> file` failes with the following error message:
cat: file: input file is output file
`tee` is a nice workaround without using any temporary files.
In this case, we'll be editing every PHP file from the current location down the tree.
You can show all the files in the vim buffer with :buffers which outputs something like,
1 %a "./config/config.php" line 1
2 "./lib/ws-php-library.php" line 0
3 "./lib/css.php" line 0
4 "./lib/mysqldb.class.php" line 0
5 "./lib/config.class.php" line 0
6 "./lib/actions.php" line 0
Press ENTER or type command to continue
If you'd like to edit ./lib/mysqldb.class.php for example, enter :b4 anytime you're editing a file. You can switch back and forth.