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).

    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

    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

    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.

    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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Install pip with Proxy
Installs pip packages defining a proxy

Split a large file, without wasting disk space
It's common to want to split up large files and the usual method is to use split(1). If you have a 10GiB file, you'll need 10GiB of free space. Then the OS has to read 10GiB and write 10GiB (usually on the same filesystem). This takes AGES. . The command uses a set of loop block devices to create fake chunks, but without making any changes to the file. This means the file splitting is nearly instantaneous. The example creates a 1GiB file, then splits it into 16 x 64MiB chunks (/dev/loop0 .. loop15). . Note: This isn't a drop-in replacement for using split. The results are block devices. tar and zip won't do what you expect when given block devices. . These commands will work: $ hexdump /dev/loop4 . $ gzip -9 < /dev/loop6 > part6.gz . $ cat /dev/loop10 > /media/usb/part10.bin

Speak the top 6 lines of your twitter timeline every 5 minutes.....
Pump up the chatter, run this script on a regular basis to listen to your twitter timeline. This is a rough first cut using several cli clips I have spotted around. There is no facility to not read those things already read to you. This could also easily be put in a loop for timed onslaught from the chatterverse, though I think it might violate several pointsof the Geneva Convention UPDATE - added a loop, only reads the first 6 twits, and does this every 5 mins.

Lookup your own IPv4 address

Text graphing ping output filter
Nasty perl one-liner that provides a sparkline of ping times. If you want a different history than the last 30, just put that value in. It (ab)uses unicode to draw the bars, inspired by . It's not the most bug-free piece of code, but what it lacks in robustness it makes up for in capability. :) If anyone has any ideas on how to make it more compact or better, I'd love to hear them. I included a ping to google in the command just as an example (and burned up 10 chars doing it!). You should use it with: $ ping | $SPARKLINE_PING_COMMAND

View any already in progress copy command in detail
If you spot a dubious looking cp command running you can use this command to view what is being copied and to where. 1234 is the PID of the cp command being passed to the lsof utility. 3r.*REG will display the file/directory that is being read/copied. 4w.*REG will display the destination it is being written to.

List the URLs of tabs of the frontmost Chrome window in OS X
This also works with Safari if you just change the application name. Replace $ window 1 with $ windows to list the URLs of tabs in all windows instead of only the frontmost window. This also includes titles: $ osascript -e{'set o to""','tell app"google chrome"','repeat with t in tabs of window 1','set o to o&url of t&"\n"&" "&title of t&"\n"',end,end}|sed \$d .

quickly backup or copy a file with bash
less symbols, tab completion. including # export SIMPLE_BACKUP_SUFFIX="_`date +%F`" in your .bashrc provides you to easily timestamp your files

Synthesize text as speech
The Festival Speech Synthesis System converts text into sound. Or: links -dump | festival --tts

Instant mirror from your laptop + webcam

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