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The Bash Fingertips: Making Your Own 'Information Centre'

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Howtos

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).

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