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The Bash Fingertips: Making Your Own 'Information Centre'

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Information Centre

FORGET bloated Web browsers. Forget so-called 'social' media (I call it social control media). They're not efficient, they eat up a lot of memory and CPU cycles, and the interfaces are not consistent (across sites). They're sufficiently distracting and they have ads. They erode privacy. They don't scale well; neither for an aging system (my laptop turns 10 in a few months) nor for users. GUIs are good in particular scenarios, but when the same things are repeated over and over again one might as well set up scripts, automating things and tailoring one's own interfaces, which is easy to achieve (relatively fast and simple) in the command line. It's also more accessible, e.g. over SSH. The pertinent tools are already out there (available for download/installation from repositories), they just need to be put together and programming skills aren't required, just batching in a bash file.

Some years ago I 'developed' a little script (I've been scripting since I was about 12). I called it getswap-sorted.sh and it just ran another script that helped me see what applications use the swap (and how much of it). For the sake of speed I like to restart applications that heavily use swap (i.e. depend on magnetic disk operations). I don't have much RAM. I never had more than 2 GB. getswap-sorted.sh just called out ./getswap.sh | sort -n -k 5 and getswap.sh comes from Erik Ljungstrom. Here it is:

#!/bin/bash
# Get current swap usage for all running processes
# Erik Ljungstrom 27/05/2011
SUM=0
OVERALL=0
for DIR in `find /proc/ -maxdepth 1 -type d | egrep "^/proc/[0-9]"` ; do
PID=`echo $DIR | cut -d / -f 3`
PROGNAME=`ps -p $PID -o comm --no-headers`
for SWAP in `grep Swap $DIR/smaps 2>/dev/null| awk '{ print $2 }'`
do
let SUM=$SUM+$SWAP
done
echo "PID=$PID - Swap used: $SUM - ($PROGNAME )"
let OVERALL=$OVERALL+$SUM
SUM=0

done

The output of getswap-sorted.sh would be something like this:


PID=1559 - Swap used: 16472 - (x-terminal-emul )
PID=21980 - Swap used: 16648 - (kwalletd5 )
PID=25548 - Swap used: 16704 - (konversation )
PID=631 - Swap used: 19336 - (kded5 )
PID=23817 - Swap used: 50048 - (pidgin )
PID=23923 - Swap used: 180312 - (thunderbird )


This helps me see which application/process number uses swap and to what degree. It's sorted by the amount of swap taken and the PID helps when I just want to kill a process from the command line (some are small and obsolete anyway).

My script, however, grew bigger over time. I added more things to it, eventually binding it to a special (fifth) mouse key, using xbindkeys -- an immensely valuable and powerful program I've used since around 2004. Extra mouse buttons always seemed worthless (anything more than three), but that's just because there was no program I needed to open or action I needed to invoke often enough. Over time I found that keeping a new terminal one click away (fourth button) and another special terminal also a click away improved my workflow/productivity. I just needed to invest some time in tailoring it. I ended up opening, temporarily, a terminal window with important information displayed, such as weather, disk space (I'm always near the limits), swap usage (I have only 2GB of RAM), uptime, real-time football scores etc. Change of wallpapers was lumped in too, for good measure...

For football tables/scores use one of the following 1) livescore-cli 2) soccer-cli and 3) football-cli.

Sadly, the above CLI football scores' tools got 'stolen' by Microsoft and need to isolate themselves GitHub, in due cource/time. I use the first of the three as it suits my needs best and does not require an API key.

The output looks like this:

 ... Fetching information from www.livescore.com ... 
Displaying Table for Barclay's Premier League
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
                                Barclay's Premier League TABLE
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 LP     Team Name               GP      W       D       L       GF      GA      GD      Pts
--------------------------------------------------------------------------------------------------
 1      Liverpool               24      19      4       1       55      14      41      61
 2      Tottenham Hotspur       25      19      0       6       51      24      27      57
 3      Manchester City         24      18      2       4       63      19      44      56
 4      Chelsea                 25      15      5       5       45      23      22      50
 5      Arsenal                 24      14      5       5       50      33      17      47
 6      Manchester United       24      13      6       5       48      35      13      45
 7      Wolverhampton Wanderers 25      11      5       9       33      32      1       38
 8      Watford                 25      9       7       9       33      34      -1      34
 9      Everton                 25      9       6       10      36      36      0       33
 10     AFC Bournemouth         25      10      3       12      37      44      -7      33
 11     Leicester City          24      9       5       10      30      30      0       32
 12     West Ham United         24      9       4       11      30      37      -7      31
 13     Brighton & Hove Albion  25      7       6       12      27      36      -9      27
 14     Crystal Palace          25      7       5       13      26      33      -7      26
 15     Newcastle United        25      6       6       13      21      33      -12     24
 16     Southampton             25      5       9       11      27      42      -15     24
 17     Burnley                 25      6       6       13      26      46      -20     24
 18     Cardiff City            25      6       4       15      22      46      -24     22
 19     Fulham                  25      4       5       16      25      55      -30     17
 20     Huddersfield Town       25      2       5       18      13      46      -33     11
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 LP = League Position   GP = Games Played       W = Wins        D = Draws       L = Lose 
 GF = Goals For         GA = Goal Against       GD = Goal Differences
--------------------------------------------------------------------------------------------------
 Champions League       Champions League qualification  Europa League
 Europa League qualification    Relegation
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Real-time scores (when matches are on):

 ... Fetching information from www.livescore.com ... 
Displaying Scores for Barclay's Premier League
----------------------------------------------------------------------------
                 Barclay's Premier League SCORES 
----------------------------------------------------------------------------
 January 29  FT     Arsenal                  2 - 1  Cardiff City           
 January 29  FT     Fulham                   4 - 2  Brighton & Hove Albion 
 January 29  FT     Huddersfield Town        0 - 1  Everton                
 January 29  FT     Wolverhampton Wanderers  3 - 0  West Ham United        
 January 29  FT     Manchester United        2 - 2  Burnley                
 January 29  FT     Newcastle United         2 - 1  Manchester City        
 January 30  FT     AFC Bournemouth          4 - 0  Chelsea                
 January 30  FT     Southampton              1 - 1  Crystal Palace         
 January 30  FT     Liverpool                1 - 1  Leicester City         
 January 30  FT     Tottenham Hotspur        2 - 1  Watford                
 February 2  FT     Tottenham Hotspur        1 - 0  Newcastle United       
 February 2  FT     Brighton & Hove Albion   0 - 0  Watford                
 February 2  FT     Burnley                  1 - 1  Southampton            
 February 2  FT     Chelsea                  5 - 0  Huddersfield Town      
 February 2  FT     Crystal Palace           2 - 0  Fulham                 
 February 2  FT     Everton                  1 - 3  Wolverhampton Wanderers
 February 2  FT     Cardiff City             2 - 0  AFC Bournemouth        
 February 3  15:05  Leicester City           ? - ?  Manchester United      
 February 3  17:30  Manchester City          ? - ?  Arsenal                
 February 4  21:00  West Ham United          ? - ?  Liverpool              
----------------------------------------------------------------------------
---------------------------------------

Now putting it all together:


feh --bg-fill --randomize /media/roy/c3fd5b6e-794f-4f24-b3e7-b4ead3722f11/home/roy/Main/Graphics/Wallpapers/Single\ Head/natgeo/* &

livescore -t bpl 

./getswap.sh | sort -n -k 5
 curl -4 http://wttr.in/Manchester
 swapon --summary | grep sda2
 df | grep sda1
uptime

sleep 10

livescore -s bpl 

sleep 40

The first line is feh choosing a wallpaper at random from a collection of award-winning National Geographic photographs. The options and the underlying parameters are self-explanatory.

The football league's table is then shown.

Next, after about 10 seconds of processing, a list of processes will show up based on swap usage (as described above)

The weather at home (Manchester) will then be shown, with colour. Right now I get:

Weather report: Manchester

     \   /     Sunny
      .-.      -5--2 °C       
   ― (   ) ―   ↑ 9 km/h       
      `-’      10 km          
     /   \     0.0 mm         
                                                       ┌─────────────┐                                                       
┌──────────────────────────────┬───────────────────────┤  Sun 03 Feb ├───────────────────────┬──────────────────────────────┐
│            Morning           │             Noon      └──────┬──────┘     Evening           │             Night            │
├──────────────────────────────┼──────────────────────────────┼──────────────────────────────┼──────────────────────────────┤
│    \  /       Partly cloudy  │      .-.      Light drizzle  │  _`/"".-.     Light rain sho…│               Mist           │
│  _ /"".-.     -4-0 °C        │     (   ).    -2-3 °C        │   ,\_(   ).   1-3 °C         │  _ - _ - _ -  0-3 °C         │
│    \_(   ).   ↑ 12-20 km/h   │    (___(__)   ↑ 17-26 km/h   │    /(___(__)  ↗ 7-14 km/h    │   _ - _ - _   ↑ 9-17 km/h    │
│    /(___(__)  20 km          │     ‘ ‘ ‘ ‘   20 km          │      ‘ ‘ ‘ ‘  16 km          │  _ - _ - _ -  13 km          │
│               0.0 mm | 0%    │    ‘ ‘ ‘ ‘    0.4 mm | 83%   │     ‘ ‘ ‘ ‘   0.4 mm | 65%   │               0.0 mm | 0%    │
└──────────────────────────────┴──────────────────────────────┴──────────────────────────────┴──────────────────────────────┘
                                                       ┌─────────────┐                                                       
┌──────────────────────────────┬───────────────────────┤  Mon 04 Feb ├───────────────────────┬──────────────────────────────┐
│            Morning           │             Noon      └──────┬──────┘     Evening           │             Night            │
├──────────────────────────────┼──────────────────────────────┼──────────────────────────────┼──────────────────────────────┤
│      .-.      Light drizzle  │  _`/"".-.     Patchy rain po…│               Cloudy         │               Cloudy         │
│     (   ).    2-6 °C         │   ,\_(   ).   3-7 °C         │      .--.     1-4 °C         │      .--.     -2 °C          │
│    (___(__)   → 16-26 km/h   │    /(___(__)  → 20-27 km/h   │   .-(    ).   → 13-23 km/h   │   .-(    ).   ↗ 9-16 km/h    │
│     ‘ ‘ ‘ ‘   14 km          │      ‘ ‘ ‘ ‘  18 km          │  (___.__)__)  20 km          │  (___.__)__)  20 km          │
│    ‘ ‘ ‘ ‘    0.3 mm | 88%   │     ‘ ‘ ‘ ‘   0.3 mm | 88%   │               0.0 mm | 0%    │               0.0 mm | 0%    │
└──────────────────────────────┴──────────────────────────────┴──────────────────────────────┴──────────────────────────────┘
                                                       ┌─────────────┐                                                       
┌──────────────────────────────┬───────────────────────┤  Tue 05 Feb ├───────────────────────┬──────────────────────────────┐
│            Morning           │             Noon      └──────┬──────┘     Evening           │             Night            │
├──────────────────────────────┼──────────────────────────────┼──────────────────────────────┼──────────────────────────────┤
│    \  /       Partly cloudy  │               Overcast       │               Overcast       │      .-.      Light drizzle  │
│  _ /"".-.     -1-3 °C        │      .--.     2-6 °C         │      .--.     6 °C           │     (   ).    1 °C           │
│    \_(   ).   ↖ 19-31 km/h   │   .-(    ).   ↑ 23-33 km/h   │   .-(    ).   ↑ 24-40 km/h   │    (___(__)   ↑ 24-40 km/h   │
│    /(___(__)  20 km          │  (___.__)__)  19 km          │  (___.__)__)  8 km           │     ‘ ‘ ‘ ‘   9 km           │
│               0.0 mm | 0%    │               0.0 mm | 0%    │               0.0 mm | 0%    │    ‘ ‘ ‘ ‘    0.3 mm | 0%    │
└──────────────────────────────┴──────────────────────────────┴──────────────────────────────┴──────────────────────────────┘


After this I am shown general memory usage and disk usage (for a particular partition) along with uptime thusly:

/dev/sda2                               partition       2097148 381128  -1
/dev/sda1        84035088   77299588   2443660  97% /
 08:03:28 up 116 days, 12:36,  7 users,  load average: 1.70, 1.40, 1.26

It will close on its own after I see what needs seeing, owing to the sleep command. It saves me the clicking (required to then close the window); it just fades away or 'expires', so to speak (until the next time the mouse button gets pressed).

How to rename files in bulk

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Consider this common scenario. A directory contains multiple files that are named using a common convention: for example, image-001.png, image-002.png, image-003.png, etc. You want to rename the files to, say, upload-001.png, upload-002.png, upload-003.png, etc.

The coders among us can write a bash script to automate the process. For expedience, this post shows how to use the built-in rename command to achieve the same goal.

Fixing OpenSuse’s Dog Awful default fonts…

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Lets not beat around the bush here, the default font rendering in OpenSuse and the default font do not an OS fit for reading make.. this can be fixed however..

Love or hate Ubuntu, out of the box it has one of the best font rendering setups of any distro and considering how much time we spend on our PC’s setting your fonts up correctly is one less headach, literally.

I’m not sure how much of these instructions I got right, however after a reboot the screen text does at least look better..

Read More

Stopping Screen Flickering on Ivy Bridge Laptops using Linux

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This is a solution to a problem which has been dogging me on every version of Linux I install on the Acer Aspire S3. I'm hoping it will help someone.

Read my solution

Forgot your Ubuntu Password? All is not lost.

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It’s always a pain when you forget your password, and i’ve often done it on an Ubuntu install. All however is not lost as a stock Ubuntu install its quite easy to reset your password

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Creating an AD Server for Free using Ubuntu and Samba

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While being a huge fan of the GNU/Linux OS I do also live in the real world which means using Active Directory Domain Controllers and Windows networks. this week however I’ve had to build for a project a stand alone AD network. This got me thinking to a project I built for a school 6 uears ago which I did the same thing with Samba on Fedora.

Remote Application launching using X11 and SSH.. Oldie but a goodie..

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Using WordPress as my central blog platform I’m very happy with it, not much to complain about, some good features, it’s very social and some nice themes. However it’s got me thinking not so much my content i’m now having a “problem” to manage it’s dealing with the replies

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Using the right tools to get your media..

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When it comes to getting what you want off the interent, its pretty fair to say, that there is an application and a set of instructions to do this. In this day and age its fair to say that getting media off the web should be the way that media companies distribute. Instead of trying to reinvent the wheel. Unfortunately they don't they bog you down with Websites, DRM, Magma and lots more.. Well This is how to get your media another way..

Standard Disclaimer: Your use of this software and configuration is at your own risk. Check the legality of downloading TV shows in your area. This post is purely for the sake of information.

.

Read more...

Big Bear's Helpful Hints-Google Docs Spreadsheets

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I like to jot down things that I learn how to do on the spur of the moment so that I can find it later.

I admit, in the 80's there was quite of bit of "herbal remedy" usage and my short term memory isn't what it could be. That's my story and I'm sticking to it.

I've decided that I might as well potentially help some other folks who might want to know about some of the things I discover, so I thought why not here?

For my very first post, I wanted to figure out how to sum cells across multiple pages in Google Docs spreadsheets.

How to get APT to work through a proxy..

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APT is the core of package management on Debian based systems, its a powerful suite of tools for getting and managing packages onto the system.

As powerful as the Apt suite is, it has problems as I found out this week working through a proxy server. Something i've recently implemented.

Read How...

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