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This command basically adds up all of the individual instances processes and gives you a grand total for used memory in that instance alone.
Computes a columns average in a file. Input parameters = column number and optional pattern.
This version prints current votes and commands for a user. Pass the user as an argument. While this technically "fits" as a one liner, it really is easier to look at as a shell script with extra whitespace. :)
Get your weather from a weather station just blocks from your home. Go to http://www.wunderground.com/wundermap/ and find a weather station near you. Click on a temperature bubble for that area. When the window pops up, click on hypertext link with the station ID, then on the bottom right of the page, click on the Current Conditions XML. Thats your link! Good luck!
Just how much space are those zillions of database logs taking up ? How much will you gain on a compression rate of say 80% ? This little line gives you a good start for your calculations.
Create one mirror copy of every lvol in the vg00 just after a cold install of an HP-UX 11.31. Cna be used also for 11.23 but remember that in 11iv2 there is no agile view so the disk will be /dev/dsk/cxtxdxs2
Makes sure the contents of "myfile" are the same contents that the author intended given the author's md5 hash of that file ("c84fa6b830e38ee8a551df61172d53d7").
xargs deals badly with special characters (such as space, ' and "). To see the problem try this:
touch 'not important_file'
ls not* | xargs rm
Parallel https://savannah.nongnu.org/projects/parallel/ does not have this problem.
This command toggles the touchpad on and off, when it's on, the right side scroll strip (annoying) and the tap-clicking are disabled, you can change this by changing occurances of 2 in the command to 0. this whole command can then be given a keyboard shortcut so that the touchpad is disableable without using a special fn key (which linux doesn't recognize on some computers) or a seperate button.
Col 1 is swapped sum in kb
Col 2 is pid of process
Col 3 is command that was issued
Might be able to do it in less steps with xmlstarlet, although whether that would end up being shorter overall I don't know - xmlstarlet syntax confuses the heck out of me.
Prompts for your password, or if you're a bit mental you can add your password into the command itself in the format "-u user:password".
This may seem like a long command, but it is great for making sure all file permissions are kept in tact. What it is doing is streaming the files in a sub-shell and then untarring them in the target directory. Please note that the -z command should not be used for local files and no perfomance increase will be visible as overhead processing (CPU) will be evident, and will slow down the copy.
You also may keep simple with, but you don't have the progress info:
cp -rpf /some/directory /other/path
You set the file/dirname transfer variable, in the end point you set the path destination, this command uses pipe view to show progress, compress the file outut and takes account to change the ssh cipher. Support dirnames with spaces.
Merged ideas and comments by http://www.commandlinefu.com/commands/view/4379/copy-working-directory-and-compress-it-on-the-fly-while-showing-progress and http://www.commandlinefu.com/commands/view/3177/move-a-lot-of-files-over-ssh
This is a handy way to circumvent the "Maximum line length of 2048 exceeded" grep error.
Once you have run the above command (or put it in your .bashrc), files can be searched using:
lgrep search-string /file/to/search
Just refining last proposal for this check, showing awk power to make more complex math (instead /1024/1024, 2^20). We don't need declare variable before run lsof, because $(command) returns his output. Also, awk can perform filtering by regexp instead to call grep. I changed the 0.0000xxxx messy output, with a more readable form purging all fractional numbers and files less than 1 MB.
Although Exim will purge frozen (undeliverable) messages over time, the command "exim -Mrm #id#" where #id# is a particular message ID will purge a message immediately. Being lazy, I don't want to type the command for each frozen message, so I wrote the one-liner to do it for me.