Say you just typed a long command like this:
rsync -navupogz --delete /long/path/to/dir_a /very/long/path/to/dir_b
but you really want to sync dir_b to dir_a. Instead of rewriting all the command line, just type followed by , and your command line will read
rsync -navupogz --delete /very/long/path/to/dir_b /long/path/to/dir_a
Just a simple way without the need of additional tools. Of course, replace eth0 with your IF. Show Sample Output
This will turn it in an infinite loop and also shows random words from a file, so it won't be the same each time and also not just a number.
Uses inotifywait from inotify-tools ( http://wiki.github.com/rvoicilas/inotify-tools/ ), that is compatible only with linux. Usefull when you work with files that have to be compiled.. latex, haml, c..
Searches backwards through your command-history for the typed text. Repeatedly hitting Ctrl-R will search progressively further. Return invokes the command. Show Sample Output
This version uses Pipes, but is easier for the common user to grasp... instead of using sed or some other more complicated method, it uses the tr command Show Sample Output
This command lets you see and scroll through all of the strings that are stored in the RAM at any given time. Press space bar to scroll through to see more pages (or use the arrow keys etc).
Sometimes if you don't save that file that you were working on or want to get back something you closed it can be found floating around in here!
The awk command only shows lines that are longer than 20 characters (to avoid seeing lots of junk that probably isn't "human readable").
If you want to dump the whole thing to a file replace the final '| less' with '> memorydump'. This is great for searching through many times (and with the added bonus that it doesn't overwrite any memory...).
Here's a neat example to show up conversations that were had in pidgin (will probably work after it has been closed)...
sudo cat /proc/kcore | strings | grep '([0-9]\{2\}:[0-9]\{2\}:[0-9]\{2\})'
(depending on sudo settings it might be best to run
sudo su
first to get to a # prompt)
Usage: t2s 'How are you?' Nice because it automatically names the mp3 file up to 15 characters Modified (uses bash manip instead of tr) t2s() { wget -q -U Mozilla -O $(cut -b 1-15
Usage examples: say hello say "hello world" say hello+world
this leaves the cursor at the bottom of the terminal screen, where your eyes are. ctrl-l moves it to the top, forcing you to look up.
Useful in shell scripts when you're trying to get the shell script name without the full path - and easier than awking or cutting. Bash pattern matching and variable manip is fun. Show Sample Output
pings a server once per second, and beeps when the server is unreachable.
Basically the opposite of:
ping -a server-or-ip.com
which would beep when a server IS reachable.
You could also substitute beep with any command, which makes this a powerful alternative to ping -a:
while true; do [ "$(ping -c1W1w1 server-or-ip.com 2>/dev/null | awk '/received/ {print $4}')" = 1 ] && date || echo 'server is down!'; sleep 1; done
which would output the date and time every sec until the ping failed, in which case it would echo.
Notes:
Requires beep package.
May need to run as root (beep uses the system speaker)
Tested on Ubuntu which doesn't have beep out of the box...
sudo apt-get install beep
Hold 'Ctrl' + 'Alt' key while selecting rectangular text area of the screen with left mouse button. Should work in any terminal screen (xterm, konsole, ...) under X, if not then try with 'Ctrl' + 'Shift' + 'Alt' or two-combination of these.
Put it in your ~/.bashrc usage: google word1 word2 word3... google '"this search gets quoted"' Show Sample Output
Though without infinite time and knowledge of how the site will be designed in the future this may stop working, it still will serve as a simple straight forward starting point.
This uses the observation that the only item marked as strong on the page is the single logical line that includes the italicized fact.
If future revisions of the page show failure, or intermittent failure, one may simply alter the above to read.
wget randomfunfacts.com -O - 2>/dev/null | tee lastfact | grep \<strong\> | sed "s;^.*<i>\(.*\)</i>.*$;\1;"
The file lastfact, can then be examined whenever the command fails.
Felt like I need to win the lottery, and wrote this command so I train and develop my guessing abilities. Show Sample Output
Every rm'ed a file you needed? Of course you haven't. But I have. I got sick of it so I created a bash function. Here it is. It'll put trashed files into a $HOME/.Trash/"date" folder according to the date. I have rm aliased to it as well in my bashrc so that I still use the rm command. It'll choke if you attempt to trash a directory if that directory name is already in the Trash. This rarely happens in my case but it's easy enough to add another test and to mv the old dir if necessary. function trash(){ if [ -z "$*" ] ; then echo "Usage: trash filename" else DATE=$( date +%F ) [ -d "${HOME}/.Trash/${DATE}" ] || mkdir -p ${HOME}/.Trash/${DATE} for FILE in $@ ; do mv "${FILE}" "${HOME}/.Trash/${DATE}" echo "${FILE} trashed!" done fi } Show Sample Output
usage: sitepass MaStErPaSsWoRd example.com description: An admittedly excessive amount of hashing, but this will give you a pretty secure password, It also eliminates repeated characters and deletes itself from your command history. tr '!-~' 'P-~!-O' # this bit is rot47, kinda like rot13 but more nerdy rev # this avoids the first few bytes of gzip payload, and the magic bytes. Show Sample Output
This is more or less the same as 'reset', but with two advantages: the initial LF character makes sure you're starting a new line to the tty driver, the final one is more reliably a line-end as CR is often unset; and second, 'stty sane' is reliable on older UNIX systems, especially Berkeley-based ones.
Looks best in an 80x24 256-color terminal emulator.
/dev/urandom is cryptographically secure, and indistinguishable from true random, as it gathers data from external sources, influenced by human timing interactions with computers, to fill the entropy pool, and hashes the input with SHA-1. As such, this is a quick way to do a "true random" fair-6 dice roll. Using this method, you could easily create passphrases with Diceware http://diceware.com. Change the head(1) count to something other than 5 for more or less numbers.
If archive has leading directory level same as archive name and you want to strip it, this command is for you.
Very simple web server listening on port 80 will serve index.html file or whatever file you like pointing your browser at http://your-IP-address/index.html for example. If your web server is down for maintenance and you'd like to inform your visitors about it, quickly and easily, you just have to put into the index.html file the right HTML code and you are done! Of course you need to be root to run the command using port 80.
This command will: 1. open an SSH tunnel to 2. go to background 3. wait for 10 seconds for the connection 4. during the 10 seconds wait it will localy run 'rdesktop' to connect to the remote host through the created SSH tunnel. Password-less log in can be achieved (when server allows it) by adding '-p ' to the 'rdesktop' command
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