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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.
» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10
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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echo 'alias monitor_off="sleep 1; xset dpms force standby"' >> ~/.bash_aliases ; . ~/.bash_aliases # now monitor_off does what you think
Converts YAML file to JSON.
Note that you'll need to install PyYAML. Also some YAML data types (like dates) are not supported by JSON).
Grabs video from dv firewire camera, saves it on file and plays it scaled down on ffplayer.
Useful to do Google+ Hangouts, and if the internet connection fails, there is still the recorded backup on the computer.
"capturefile" is the filename prefix that will be stored on disc.
This allows you to search through your history using the up and down arrows ? i.e. type "cd /" and press the up arrow and you'll search through everything in your history that starts with "cd /".
this command extends your logical volume. then it does a resize2fs on it as well. added the -r switch to make it launch resize.
So I had this 2TB Seagate external disk/USB enclosure which by default would spin-down its internal drive (it enters a standby mode) after four minutes of inactivity.. Spinning-up the inactive drive was an annoying delay when accessing files and also it severely interfered with NFS.. SCT stands for "Standby Condition Timer".
To completely disable SCT:
sdparm --clear STANDBY -6 /dev/sdb
To return to original (default) SCT settings:
sdparm -D -p 0x1a -6 /dev/sdb
To verify the settings (before and after):
sdparm -a /dev/sdb
No need for vendor-provided MSWIN tools, etc.
Install the Linux kernel headers for currently running kernel version on Debian-based systems via apt-get
Your computer's name is raspberrypi and you want to rename it to pita1.
This command will change both the hostname and the name used for netwrk communications.
A commandline version of the notepad in a browser: http://www.commandlinefu.com/commands/view/12161/notepad-in-a-browser-type-this-in-the-url-bar
All credit to the origional author of this fantastic command, whos only failing as most of the comments pointed out was that it wasn't a command... well, now its a command. Send all upvotes to dtlp747.
If you are on your bed, waching a movie or if you are downloading something, but you whant to sleep. You can use these easy command to power off after X time. The time is in sec. if you whant to wait 1 H, use:
sleep 3600; poweroff
To decrypt: openssl aes-256-cbc -d -in secrets.txt.enc -out secrets.txt.new
Reference: http://tombuntu.com/index.php/2007/12/12/simple-file-encryption-with-openssl
Optional parameter -a makes output base64 encoded, can be viewed in text editor or pasted in email
Find all .gz files and recompress them to bz2 on the fly. No temp files.
edit: forgot the double quotes! jeez!
Adjust the --resolution and --mode as required (if these options are available for your scanner).
The size options (-x, -y, -imageheight, -imagewidth) are for US letter paper. For A4, I think the command would be:
scanimage -p --resolution 250 --mode Gray -x 210 -y 297 | pnmtops -imageheight 11.7 -imagewidth 8.3 | ps2pdf - output.pdf
Found this useful query at http://id.motd.org/pivot/entry.php?id=22. The b.parent=2 in the command refers to the bookmarks folder to extract. See the source webpage for additional info.
parallel can be installed on your central node and can be used to run a command multiple times.
In this example, multiple ssh connections are used to run commands. (-j is the number of jobs to run at the same time). The result can then be piped to commands to perform the "reduce" stage. (sort then uniq in this example).
This example assumes "keyless ssh login" has been set up between the central node and all machines in the cluster.
bashreduce may also do what you want.
Oneliner to run commands on multiple servers over ssh.
- First parameter "$1" is the command you want to execute remotely.
( It can be multiple commands e.g. "hostname;uptime")
- Second parameter "${@:2}" represents the remote host/s you want to run the command/s on.