Commands by UnixNeko (4)

  • PING parameters c 1 limits to 1 pinging attempt q makes the command quiet (or silent mode) /dev/null 2>&1 is to remove the display && echo ONLINE is executed if previous command is successful (return value 0) || echo OFFLINE is executed otherwise (return value of 1 if unreachable or 2 if you're offline yourself). I personally use this command as an alias with a predefined machine name but there are at least 2 improvements that may be done. Asking for the machine name or IP Escaping the output so that it displays ONLINE in green and OFFLINE in red (for instance).


    9
    ping -c 1 -q MACHINE_IP_OR_NAME >/dev/null 2>&1 && echo ONLINE || echo OFFLINE
    UnixNeko · 2012-02-09 06:30:55 7
  • Extracting .gz files and placing the output in another directory in one command line is convenient thing. I just followed some how-to to install Nagios on Ubuntu Lucid Lynx but they give the method to install from archives. I wished to install from the repository. If you do so some files are missing. I've not tested yet but this is an example command line I did to extract sudo sh -c 'gunzip -c /usr/share/doc/nagios3-common/examples/template-object/templates.cfg.gz > /etc/nagios3/objects/templates.cfg' We need privilege to write the destination file. Show Sample Output


    0
    sudo sh -c 'gunzip -c source.gz > destination'
    UnixNeko · 2011-07-05 23:51:01 1
  • Can be useful to rip a CD. Show Sample Output


    -1
    ripit -c 0 --outputdir $1 --nosubmission
    UnixNeko · 2011-06-12 12:29:26 0
  • I have some problems with gnome panel which does not load completely leaving me without the actual GUI. This commands helps to kill the gnome-panel process then it should be relaunch automatically.


    -2
    pgrep -lf gnome-panel | awk '{if ($2=="gnome-panel") print $1}' | xargs kill -9
    UnixNeko · 2011-06-12 12:23:27 2

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a function to find the fastest DNS server
http://public-dns.info gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in 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"

Remove CR LF from a text file
Remove CR LF (CRLF) from a text file. use man:tr to get more info about removing other characters from a file. and even character to character replacements.

Install pip with Proxy
Installs pip packages defining a proxy

Geolocate a given IP address
GeoIP Needs to be installed. Can be done from some distro's or via MaxMind.com for free. There even is a free city database availabble. If the GeoLiteCity is downloaded and installed it will also find more information $ geoiplookup -f /var/lib/GeoIP/GeoLiteCity.dat commandlinefu.com GeoIP City Edition, Rev 1: US, NJ, Absecon, 08201, 39.420898, -74.497704, 504, 609

Revert an SVN file to previous revision
Kudos to xakon.

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

output list of modifications for an svn revision
url can be a working copy or url to a svn repository, revision is any valid revision number for that branch.

Collect a lot of icons from /usr/share/icons (may overwrite some, and complain a bit)
In other way of xargs, only with find -exec

Create a false directory structure for testing your commands
This will make a false directory with the same file names as whatever directory you choose. This is wise to use when testing scripts that alter contents, filenames, or move files. I wrote this after an OOPS I made when renaming a directory of JPGs, PNGs, PSDs that were mixed. I recommend this as I lost over 2000 vacation pictures and some graphics I designed for software and web sites. :( NOTE: This only creates name copies, that data itself is not copied.


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