commandlinefu.com is the place to record those command-line gems that you return to again and again.
Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.
If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/
You can sign-in using OpenID credentials, or register a traditional username and password.
First-time OpenID users will be automatically assigned a username which can be changed after signing in.
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,…):
Subscribe to the feed for:
This is a safest variation for "sitepass function" that includes a SALT over a long loop for sha512sum hash
Even shorter. Stolen from comment posted by eightmillion.
The same command, but with a base64 filter, more forgiving for special characters than tr.
This command deletes the "newline" chars, so its output maybe unusable :)
It's works only when you replace '\n' to ONE character.
displays current time in "binary clock" format
(loosely) inspired by: http://www.thinkgeek.com/homeoffice/lights/59e0/
.... - 1st hour digit: 0
*..* - 2nd hour digit: 9 (8+1)
.*.. - 1st minutes digit: 4
*..* - 2nd minutes digit: 9 (8+1)
PROMPT_COMMAND='echo "10 i 2 o $(date +"%H%M"|cut -b 1,2,3,4 --output-delimiter=" ") f"|dc|tac|xargs printf "%04d\n"|tr "01" ".*"'
Of course, this command must be executed at a GRID User Interface
lhcb - name of your VO, substitute it with the one you are interested it.
Reads 4 bytes from the random device and formats them as unsigned integer between 0 and 2^32-1.
Article mentions what each part of the command is responsible for.
Gives the same results as the command by putnamhill using nine less characters.
255 Max Characters CommandLineFu for $dellurl='http://support.dell.com/support/topics/global.aspx/support/my_systems_info/en/details?c=us&cs=04&l=en&s=hied&ServiceTag='
This command is primarily going to work on linux boxes.
and needs to be changed, for example
Note: Replace 200000 with drive bytes/512, and /dev/sdx with the destination drive/partition. ;)
Note: You may need to install pipebench, this is easy with "sudo apt-get install pipebench" on Ubuntu.
The reason I hunted around for the pieces to make up this command is that I wanted to specifically flip all of the bits on a new HDD, before running an Extended SMART Self-Test (actually, the second pass, as I've already done one while factory-zeroed) to ensure there are no physical faults waiting to compromise my valuable data. There were several sites that came up in a Google search which had a zero-fill command with progress indicator, and one or two with a fill-with-ones command, but none that I could find with these two things combined (I had to shuffle around the dd command(s) to get this to happen without wasting speed on an md5sum as well).
For reference, these are the other useful-looking commands I found in my search:
Zero-fill drive "/dev/sdx", with progress indicator and md5 verification (run sudo fdisk -l to get total disk bytes, then divide by 512 and enter the resulting value into this command for a full wipe)
dd if=/dev/zero bs=512 count=<size/512> | pipebench | sudo tee /dev/sdx | md5sum
And this command for creating a file filled with ones is my other main source (besides the above command and man pages, that is - I may be a Linux newbie but I do read!):
tr '\000' '\377' < /dev/zero | dd of=allones bs=1024 count=2k
Hope someone finds this useful! :)
Tee can be used to split a pipe into multiple streams for one or more process to work it. You can add more " >()" for even more fun.