Computing

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Free DNS @ afraid.org OzHosting HTML4.01 (local copy) HTML4.01 (web version) Telstra Gateway
WhoIs database Ubuntu Python 2.7 Connection Speed Test

Literate Programs

Setup HouseMade JMR Cron Jobs Photos

How The Web Pages were One

These web pages have gone through a number of interations. This Web Page documents the story.

Context

My new house uses a 114.6Mbps download/2.4Mbps upload internet connection (Telstra Broadband Cable). See the Telstra Connection Speed Test to check your connection. Mind you, the modem used is a Telstra Gateway Max, which has had some very bad reviews ! My experience mirrors those described in those ppages. My own workaround is to set up static IPs for the local network in the network connection configurations (System Preferences->Network on Macs, UP-DOWN icon->Edit Connections on Linux). But safe to say, I don't think we will switch our Bigpond connection across to our old house when we return.

My old house uses a 2.9Mbps download/0.74Mbps upload internet connection (Internode ADSL2+), using a Billion 7800N modem, which worked fine throughout its lifetime (in contrast to Telstra!)

I have a range of computers. Keeping track of them (and maintaining them!) can be a headache. So I've started compiling a list of current machines. There are also a number of web servers (such as the one you are reading right now on ajhurst.org@albens). The general principle used to name them is

  1. railway junctions in Victoria (on-site and laptops)
  2. eucalyptus trees (off-site)
  3. disused railway stations in Paris (micro-computers)
Here is a list of the computers/servers, their URLs, DNS sites, use and model:

Server Name Use Model System URL DNS
albens Off-site server virtual linux box leased from Digital Ocean, Ubuntu 14.04 IP: 45.55.18.15
DN: albens.ajhurst.org
Afraid
auteuil chook house controller
(not in use during renovations)
Beagle Bone Black Ubuntu ? IP: 10.0.0.117 -
bittern laptop
(available, not in regular use)
Apple MacBook Pro 15" OSX 10.6.8 IP: 10.0.0.109 -
dimboola Mac OSX desktop system Apple iMac 27" OSX 10.6.8 IP: 10.0.0.110 (local) -
echuca Ubuntu desktop system Apple iMac 21" Ubuntu 16.04 IP: 10.0.0.107 -
eregnans church wiki server (wiki.gwuc.org.au) virtual linux box leased from Rackspace, Ubuntu 14.04 IP: 173.203.214.77
DN: eregnans.ajhurst.org
Afraid
fat-controller train computer
(currently powered off)
Pentium Ubuntu ? IP: 10.0.0.104 -
hamilton current laptop Apple MacBook Pro (Retina 13") OSX 10.10.5 IP: 10.0.0.118 -
lilydale laptop ACER Aspire S7 11" Ubuntu 14.04 IP: 10.0.0.112 -
spencer Main home server Silverstone RM720 with ASUS Z170-AR motherboard Ubuntu 16.04 IP: 10.0.0.112
IP: 150.101.166.83
DN: ajh.co,
101.167.106.147
DN: ajh.id.au
OzHosting
wolseley General purpose system
(currently powered off)
HP Compaq Ubuntu 13.10 IP: 10.0.0.106 -
albens
Virtual server maintained by Digital Oceans. Used for off-site serving, mail and various maintenance tasks.
bittern
old laptop (currently out of use)
dimboola
My home desktop iMac (Mac OSX 10.6.8) This is now used only for mail, and is to be decommissioned (or turned into a Linux box).
echuca
My home desktop iMac (Ubuntu 16.04) Desktop machine of preference.
eregnans
RackSpace virtual Linux box (Ubuntu), maintained to supply wiki services to the Glen Waverley Uniting Church:
fat-controller
An old Intel box running an old version of Ubuntu. Used to control the model railway, but decommissioned until the railway is restored.
hamilton
new laptop. Much lighter than bittern, and used for travelling. Has Ubuntu running as a virtual machine under Mac OSX.
lilydale
Interesting history. Bought explicitly to run Linux, and to be used as my regular laptop. But I found the trackpad and keyclick very frustrating to use, and it saw service as the house computer for a year or so. Now back in service as a laptop, but not regularly used.
spencer
disk farm and house server. A 32TB (6TBx4 + 8TBx1 drives) butter fs system is used in a RAID1 configuration to store all household data and backups for other machines. It also houses a number of other smaller disks for use in day-to-day use (e.g., TV and Photographs)
wolseley
Previously used as a house server. Now too slow for much at all.

Hints and Fixes

Karabiner Keys

If you want to know what name to give various keys when redefining them in Karabiner, please refer to this page.

Mail Folder Sort Order not maintained

My (Mac OSX) mail folders suddenly started being displayed in non-alpha order whenever I added a new folder. I'm not the only person to notice this - there is an Apple Disscussion Thread on it. The original page is available, but in case it disappears, I've saved a copy at FixMailSort.html. Here is the gist:

Kenji Kono

Re: Mail Not Sorting new Folders Added Alphbetically
Jan 28, 2010 8:05 PM (in response to Matt Garr)
Hi,

I'm not sure, but I suspect the new Snow Leopard feature ...
http://www.apple.com/macosx/refinements/enhancements-refinements.html#mail
... that lets you move folders around manually might be what's causing
the weird behavior.

In Leopard, you could move a folder inside another folder but,
otherwise, they would always stay in alphabetical order, I think.

Anyways, in Snow Leopard (and Leopard for that matter), there's an
invisible file around ~/Library/Mail/<name of your email
account>/.mboxCache.plist It seems to keep a list of the mboxes in
that folder/account. In Snow Leopard, the first time you manually move
an mbox out of alphabetical order, a new key called
MailboxDisplayOrder seems to get created in that plist for all the
existing "non-special" (i.e. not INBOX, Sent, Drafts, etc.) mboxes in
that folder. Once that key exists, it seems like new folders get
appended to the end of the order.

I don't know the right way to fix the problem though. I'm really just
posting my observations, based on what I'm seeing on my computer. I'd
be very careful about manually messing with invisible files in your
mail, especially if you don't have a good backup. (No idea if you can
restore an invisible file with Time Machine.) A lot of this is
guesswork. But I thought maybe it'd help someone.

Later,
k
        
The solution is to delete the offending .mboxCache.plist file. You should exit Mail before you do this, and it will get rebuilt next time you run Mail.

Invisible files

When I first obtained a Mac, using (IIRC) Mac OS 3.1 or thereabouts, my son discovered that there was a resource fork bit that made files invisible. He delighted in changing that bit on files that I used, so I rapidly discovered how to unset it again. That facility is still there in OS X, so I have documented that little lurk to avoid any future mischief.

To make a file invisible:

$ /Developer/Tools/SetFile -a V file-name

(upper case V)

To make a file visible:

$ /Developer/Tools/SetFile -a v file-name

(lower case v)

Safari Plug-Ins

I installed/updated my Adobe reader, and the next time I used Safari, it asked me if I wanted to install the Adobe plug-in to make Safari use the Adobe reader for PDF files. I said yes at the time, but after a bit of use, found it too slow. Granted, it does have more features, but not the one I wanted, which was to open it up outside the browser. With the standard Preview option, this was just a right-mouse pull down "Open in Preview", very convenient. But how to get back to Preview?

A bit of Googling revealed the answer. In Tiger (10.4) and Leopard (10.5), there is a folder /Library/Internet Plug-Ins/ that contains all the plug-ins. Remove the one called AdobePDFViewer.plugin, restart Safari, and you are back with Preview.

And while on the subject of Safari, here's how to change the default browser preference:

  1. Open Safari (/Applications).
  2. From the Safari menu, choose Preferences.
  3. Click the General button.
  4. Choose a different browser from the Default Web Browser pop-up menu.
(from http://support.apple.com/kb/HT1637)

OpenOffice recovery documents

When Open Office (version 3) "loses" its recovery files, and keeps asking to recover (non-existent) files, edit the file: /Users/ajh/Library/ApplicationSupport/OpenOffice.org/3/user/registry/data/org/openoffice/Office/Recovery.xcu to delete the element nodes containing the offending file path. Then save this file, and restart OpenOffice.

Finding out the screen resolution

I run a number of different displays, and when starting up various programs I need to know the current screen resolution. This little script does the trick:

        #!/bin/bash
        #
        # screenres      determine screen resolution 'HEIGHTxWIDTH'
        # screenres -w   determine screen resolution 'WIDTH'
        # screenres -h   determine screen resolution 'HEIGHT'
        # 
        res=`xdpyinfo | awk '/dimensions/ {print $2}'`
        if [ "$1" = '-h' ] ; then
          # extract height and print
          expr "$res" : '.*x\([0-9]*\)'
        elif [ "$1" = '-w' ] ; then
          # extract width and print
          expr "$res" : '\([0-9]*\)'
        else
          # print full resolution
          echo $res
        fi
      

Apple's X11 Cut and Paste

Apple did a Great Thing in making X11 available as part of OS X, but it was always going to be a difficult task, given the different "look and feel" of the two user interfaces. To try and fix the inconsistency between the OS X cut and paste, and X11's cut and paste, check out this Fix for Apple's X11 Cut and Paste

Keyboard Shortcuts on Booting

To find out all those nifty keyboard things when things go wrong, here's a page to describe the Keyboard Startup Shortcuts.

Automatically changing the Desktop Picture in Snow Leopard

I had a cool little script that changed the desktop background picture (aka wallpaper) automatically, according to parameters stored in an XML file. See this Multithreaded Image Viewer for details. Most of it was pretty plain python programming (I even set it as an exercise in concurrent programming one year), but it relied upon a shell script setBackground.sh that used an Applescript script to do the actual picture change via a set desktop picture to file MyPicFile.

Here's what that script looks like:

      #!/bin/sh
      #
      # simple shell script to set the backgroup image
      # uses an Applescript call to do the actual work
      # call:
      #  setBackground.sh <imageFilename>
      
      FILE=$1
      
      #echo $FILE >>output.txt
      
      /usr/bin/osascript <<END
      tell application "Finder"
        set myFile to POSIX file "$FILE" as string
        set desktop picture to file myFile
      end tell
      END
    

But then it broke in Snow Leopard, for reasons I do not understand. Attempts to find how to do this task via much Googling also proved fruitless. While fiddling around with the standard Apple Change Desktop Background pop-up memu, I hit on the idea of having a folder with only one image in it, and setting the reload time to 5 seconds, the shortest reload time.

Hence this new script for setBackground.sh. It looks like this:

      #!/bin/sh
      FOLDER=/Users/ajh/Pictures/Desktop
      FILE=$1
      
      rm $FOLDER/*
      ln -s $FILE $FOLDER
    

I used a soft link without thinking about why. It could be a hard link, I guess.

(20100330:094441) And this is not perfect by any means. It breaks on my laptop when I put it to sleep, or change locations, or both, or neither (hard to say which, since it seems very erratic!) Every so often I have to invoke "Change Desktop Background", and reselect the folder in which the temporary item is placed.

(20101216:160200) The behaviour in Snow Leopard is now consistent with Leopard again. I don't know what happened, but I now use the script identified at the beginning of this item. I'm keeping the rest of the story here just in case.

Filename extensions

I noticed while using Keynote that my filename extensions were getting thrown away. I was not the only one to be puzzled by this behaviour, so I thought I should comment on the fix required.

Go to the Finder Preferences, and click the Advanced tab. Under Snow Leopard, the top check box should be "Show all filename extensions". If this is unchecked, click it, and your filename extensions will magically reappear!

For some reason, Apple appears to have changed the default value on this from Leopard to Snow Leopard, leaving many users puzzled as to what is going on.

Fixing the X11 "Focus Follows Mouse" hassle

In a terminal, type:

    defaults write org.x.X11 wm_ffm -bool true
and then restart X11.

Unix Stuff

To set the system timezone to Melbourne

      $ sudo bash
      $ cd /etc
      $ ln -sf /usr/share/zoneinfo/Australia/Melbourne localtime
    

Moving to Ubuntu

I got the irrits with Apple and have sworn not to buy a new system or upgrade the systems I have, preferring instead to move (back) to Linux as necessity demands. But Ubuntu has its own irrits, too! This is a log of things that I have fixed.

Virtual desktops

Mac OSX calls them "Spaces", Ubuntu calls them "Workspaces". I prefer "Virtual Desktops". Oh well. You can't please everyone.

The hassle is that there is no clear way of driving the number of them, and how to switch between them.

Setting Up
Go into the System Settings > Appearance > Behaviour, and check the box "Enable workspaces". This sets up the default 2x2 workspaces.
Changing the Number of Workspaces
Make sure that "CompizConfig Settings Manager" is installed (use the "Ubuntu Software Centre" to search for and install this). Then follow General Options > Desktop Size, and set the Horizontal Virtual Size and Vertical Virtual Size to your preferences. Close the CCSM.
Showing the Virtual Desktops
You show see an icon in the launcher that looks like this one (it may have a background colour to match the launcher). If you click this icon, a representation of the workspaces available will be shown. Click it again to dismiss, or click inside any of the workspaces to switch to that workspace.

Keyboard Shortcut to Switch Workspace
CTRL-ALT-arrow will change to the next workspace in the direction of arrow.
This page is copyright, and maintained by John Hurst. 963 accesses since
24 Aug 2016
My PhotoMy PhotoTrain Photo

Local servers: Localhost Dimboola Spencer Lilydale Echuca (Note that these are only accessible on my local network.)
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