Commands by mrwill (7)

  • this command will beep like an alarm for one minute from 18:57. you can change "1857" to your desired time. you should have alsa-oss package installed, and you should also be root or part of "audio" group.


    -1
    while true; do while [ `date +%H%M` == "1857" ] ; do sleep 1s; yes | head -n 2000 > /dev/dsp; done; done;
    mrwill · 2011-04-23 14:44:26 5

  • 0
    equery belongs $( which mv )
    mrwill · 2011-02-11 22:50:15 0

  • -3
    rename .txt .md *.txt
    mrwill · 2010-12-19 20:04:37 3
  • you should have the "most" package installed. I like it because it is colorful and easier to read. alternatively you can use "less" instead of "most". you can also add this to your ~/.bashrc to make it permanent.


    1
    export MANPAGER='most'
    mrwill · 2010-07-02 08:35:36 2

  • 0
    ifconfig eth0 | awk '/inet / {print $2}' | cut -d ':' -f2
    mrwill · 2010-06-30 08:52:01 0
  • if you want to see all information about a package use: rpm -qi pkgname full list of querytags can be accessed by the command: rpm --querytags you can also customize the query format how ever you like with using more querytags together along with escape sequences in "man printf"! you can also use more than one package name. for example this command shows name and version in to columns: rpm -q --queryformat %-30{NAME}%{VERSION}\\n pkg1 pkg2 Show Sample Output


    1
    rpm -q --queryformat %{VERSION}\\n pkgname
    mrwill · 2010-06-03 01:54:17 0
  • you can also pipe it to "tail" command to show 10 most memory using processes. Show Sample Output


    13
    ps aux --sort=%mem,%cpu
    mrwill · 2009-10-10 22:48:51 0

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convert video format to youtube flv format

Uniquely (sort of) color text so you can see changes
Colorify colors input by converting the text to a number and then performing modulo 7 on it. This resulting number is used as the color escape code. This can be used to color the results of commands with complex outputs (like "482279054165371") so if any of the digits change, there's a good chance the color will change too. I say good chance because there's only 7 unique colors here, so assuming you were watching random numbers, there would be a 6/7 chance that the color would change when the number changed. This should really only be used to help quickly identify when things change, but should not be the only thing relied upon to positively assert that an output has not changed.

Create a script of the last executed command
Sometimes commands are long, but useful, so it's helpful to be able to make them permanent without having to retype them. An alternative could use the history command, and a cut/sed line that works on your platform. $history -1 | cut -c 7- > foo.sh

Who has the most Apache connections.
This will tell you who has the most Apache connections by IP (replace IPHERE with the actual IP you wish to check). Or if you wish, remove | grep -c IPHERE for the full list.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Retrieve "last modified" timestamp of web resource in UTC seconds
This command line assumes that "${url}" is the URL of the web resource. It can be useful to check the "freshness" of a download URL before a GET request.

Clear terminal Screen
Probably the quickest / easiest way to clear the screen.

Convert spaces in file names to underscores

Count lines of code across multiple file types, sorted by least amount of code to greatest
Gives you a nice quick summary of how many lines each of your files is comprised of. (In this example, we just check .c, .h, .php and .pl). Since we just use wc -l to count, you'll just get a very rough estimate of how many lines of actual code there are. Use a more sophisticated algorithm instead if you need to.

Doing some floating point calculations with rounding (e.g. at the 3rd decimal)


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