If you typed 'sl', put the cursor on the 'l' and hit ctrl-t to get 'ls'.
file(1) can print details about certain devices in the /dev/ directory (block devices in this example). This helped me to know at a glance the location and revision of my bootloader, UUIDs, filesystem status, which partitions were primaries / logicals, etc.. without running several commands.
See also:
file -s /dev/dm-*
file -s /dev/cciss/*
etc..
Show Sample Output
Show all columns except 5th. This might help you save some typing if you are trying to exclude some columns from the output.
grep searches through a file and prints out all the lines that match some pattern. Here, the pattern is some string that is known to be in the deleted file. The more specific this string can be, the better. The file being searched by grep (/dev/sda1) is the partition of the hard drive the deleted file used to reside in. The ?-a? flag tells grep to treat the hard drive partition, which is actually a binary file, as text. Since recovering the entire file would be nice instead of just the lines that are already known, context control is used. The flags ?-B 25 -A 100? tell grep to print out 25 lines before a match and 100 lines after a match. Be conservative with estimates on these numbers to ensure the entire file is included (when in doubt, guess bigger numbers). Excess data is easy to trim out of results, but if you find yourself with a truncated or incomplete file, you need to do this all over again. Finally, the ?> results.txt? instructs the computer to store the output of grep in a file called results.txt. Source: http://spin.atomicobject.com/2010/08/18/undelete?utm_source=y-combinator&utm_medium=social-media&utm_campaign=technical
This function displays the latest comic from xkcd.com. One of the best things about xkcd is the title text when you hover over the comic, so this function also displays that after you close the comic.
To get a random xkcd comic, I also use the following:
xkcdrandom(){ wget -qO- dynamic.xkcd.com/comic/random|tee >(feh $(grep -Po '(?<=")http://imgs[^/]+/comics/[^"]+\.\w{3}'))|grep -Po '(?<=(\w{3})" title=").*(?=" alt)';}
This command creates and burns a gapless audio CD with 99 tracks. Each track is a 30 second sine wave, the first is 1 Hz, the second 2 Hz, and so on, up to 99 Hz. This is useful for testing audio systems (how low can your bass go?) and for creating the constant vibrations needed to make non-Newtonian fluids (like cornstarch and water) crawl around.
Note, this temporarily creates 500MB of .cdda files in the current directory. If you don't use the "rm" at the end of the command, you can burn more disks using
cdrdao write cdrdao.toc
Prerequisites: a blank CD-R in /dev/cdrw, sox (http://sox.sourceforge.net/), and cdrdao (http://cdrdao.sourceforge.net/). I'm also assuming a recent version of bash for the brace expansion (which just looks nicer than using seq(1), but isn't necessary).
Show Sample Output
this bzips a folder and transfers it over the network to "host" at 777k bit/s.
cstream can do a lot more, have a look http://www.cons.org/cracauer/cstream.html#usage
for example:
echo w00t, i'm 733+ | cstream -b1 -t2
hehe :)
sudo apt-get install sl
man sl
Show the number of failed tries of login per account. If the user does not exist it is marked with *. Show Sample Output
I save this to bin/iptrace and run "iptrace ipaddress" to get the Country, City and State of an ip address using the http://ipadress.com service. I add the following to my script to get a tinyurl of the map as well: URL=`lynx -dump http://www.ip-adress.com/ip_tracer/?QRY=$1|grep details|awk '{print $2}'` lynx -dump http://tinyurl.com/create.php?url=$URL|grep tinyurl|grep "19. http"|awk '{print $2}'
Compress information DBs of firefox to speed up the launch of browser.
Sed stops parsing at the match and so is much more effecient than piping head into tail or similar. Grab a line range using
sed '999995,1000005!d' < my_massive_file
Why remember? Generate! Up to 48 chars, works on any unix-like system (NB: BSD use md5 instead of md5sum) Show Sample Output
-n switch keeps empty columns If your distribution does not ship with a recent column version that supports -n you can use this alternative: perl -pe 's/(^|;);/$1 ;/g' file.csv | column -ts\; | less -S Change the delimiter to your liking.
4 random words are better than one obfuscated word http://xkcd.com/936/ Show Sample Output
If you have the fdupes command, you'll save a lot of typing. It can do recursive searches (-r,-R) and it allows you to interactively select which of the duplicate files found you wish to keep or delete.
If you provide the option -t to the script command and redirect stderr into a file, the timing information on what is going on on the terminal, is also stored. You can replay the session via the scriptreplay command, where you can also provide a speedup factor (see the man page for details). Great for demonstration purposes ...
Now type Ctrl-l and it will list all files
This makes an alias for a command named 'busy'. The 'busy' command opens a random file in /usr/include to a random line with vim. Drop this in your .bash_aliases and make sure that file is initialized in your .bashrc.
If you have some drive imaging to do, you can boot into any liveCD and use a commodity machine. The drives will be written in parallel.
To improve efficiency, specify a larger block size in dd:
dd if=/dev/sda bs=64k | tee >(dd of=/dev/sdb bs=64k) | dd of=/dev/sdc bs=64k
To image more drives , insert them as additional arguments to tee:
dd if=/dev/sda | tee >(dd of=/dev/sdb) >(dd of=/dev/sdc) >(dd of=/dev/sdd) | dd of=/dev/sde
This command lets you select from 10 different BBC stations. When one is chosen, it streams it with mplayer. Requires: mplayer with wma support.
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