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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,…):
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lists all files that are opened by processess named $processname
egrep 'w.+REG' is to filter out non file listings in lsof, awk to get the filenames, and sort | uniq to remove duplciation
displays the output of ls -l without the rest of the crud. pretty simple but useful.
We don't use CPU scaling, but just in case you do, there is something interesting to note. If you look at the /proc/cpuinfo, the speed listed is current running speed of the processors and not the real speed of the chip.
man dmidecode [look for type]
Provides numerically sorted human readable du output. I so wish there was just a du flag for this.
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