Commands by Risthel (2)

  • Reload all sysctl variables without reboot

    Reload all defined kernel variables from /etc/sysctl.conf(if no parameter after -p is given) without the old myth "Ah, you'll need to reboot to apply those variables"... Show Sample Output


    1
    /sbin/sysctl -p
    Risthel · 2013-02-14 12:48:26 4
  • Export a postgresql query into csv file

    This command will "su" the execution of the command to the postgres user(implies that you are already logger as root), and export the result of the query to a file on the csv format. You'll need to adequate the fields and database information to one of your choice/need. Show Sample Output


    0
    # su -c "psql -d maillog -c \"copy (select date,sender,destination,subject from maillog where destination like '%domain.com%') to '/tmp/mails.csv' with csv;\" " postgres
    Risthel · 2013-02-13 13:03:17 5

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. 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.

Share Your Commands

Check These Out

FizzBuzz in one line of Bash
The (in)famous "FizzBuzz" programming challenge, answered in a single line of Bash code. The "|column" part at the end merely formats the output a bit, so if "column" is not installed on your machine you can simply omit that part. Without "|column", the solution only uses 75 characters. The version below is expanded to multiple lines, with comments added. for i in {1..100} # Use i to loop from "1" to "100", inclusive. do ((i % 3)) && # If i is not divisible by 3... x= || # ...blank out x (yes, "x= " does that). Otherwise,... x=Fizz # ...set x to the string "Fizz". ((i % 5)) || # If i is not divisible by 5, skip (there's no "&&")... x+=Buzz # ...Otherwise, append (not set) the string "Buzz" to x. echo ${x:-$i} # Print x unless it is blanked out. Otherwise, print i. done | column # Wrap output into columns (not part of the test).

Get the version of sshd on a remote system
I used this to confirm an upgrade to an SSH daemon was successful

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Real time satellite wheather wallpaper
Changes the wallpaper to the last satellite image. Tha url above shows latin america. Seek the best url for your location Now I have a usefull background image in my desktop I use it inside kalarm updating every 15 minutes. May be done with 'watch' instead It s an option to xplanet ( kde ) and xearth needs xli , curl

Join lines split with backslash at the end
Joins each line that end with backslash (common way to mark line continuation in many languages) with the following one while removing the backslash.

show git logging
shows some logging for the git repo.

extract email adresses from some file (or any other pattern)
Simply more email-adresses matched

Show crontabs for all users
This is flatcaps tweaked command to make it work on SLES 11.2

Move all but the newest 100 emails to a gzipped archive

download 10 random wallpapers from google
you may want &hl=en for &hl=es for the language you may want imgsz=xxlarge for imgsz=large or whatever filter you may want q=apples or whatever

Stay in the loop…

Follow the Tweets.

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

Subscribe to the feeds.

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: