Author Archives: Leigh

ssh-agent

On Linux systems it’s common to use ssh-agent (manpage) to store SSH keys. When you run the agent its output can be used to configure it within your shell. The variables defined allow ssh and ssh-add to find the agent once it’s started. I use an Ubuntu VM, and regularly log in using PuTTY. It’s […]

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Creating a VM to mimic EC2

I spend a lot of time working with Amazon’s EC2 (Elastic Compute Cloud) virtual servers. Configuring a new server takes up a surprisingly large amount of time when done manually, and so I use Puppet to automate the process. This works pretty well, but after creating lots of new configuration code I always think it’s worth […]

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Exotic Data Structures

I came across this recent comment on Hacker News today, and thought the data structures therein worth advertising further: Smushed list Size O(1). The smushed list is a list of variables (of the same type), stored in a single variable of that type. To produce the smushed list, simply XOR all the elements of the list together, […]

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PHP documentation and Sphinx

Documentation is important, but commonly forgotten. Writing any code requires filling your brain with information – what the language is doing – what the API you’re calling is doing – what you want the code to do – and most of this information will fall out again a few days later. A month later a bug […]

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Developing in a Linux Virtual Machine on Windows (3)

This post is part of a series about my development stack – I use an Ubuntu Server VM running on Windows. Part 1 showed how to set up the VM Part 2 demonstrated how we could share code on the host system with the guest in order to execute it in a Linux environment There’s some […]

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Developing in a Linux Virtual Machine on Windows (2)

This is the continuation of a previous post where we set up an Ubuntu virtual machine in VMWare Player on a Windows host. To recap, what we’ve got so far is: An easily-accessible Ubuntu server. Folders on the host shared with the guest. We can edit code on the host machine and then test the changes in […]

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Database design 101: Is your field big enough?

When designing a database schema, it’s worth trying to choose sensible sizes for each column. It’s obviously crucial to make sure that your field gives enough space to accommodate the data you want to store in it, but it’s good to keep the sizes down as far as possible in order to improve performance. Increasing […]

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Virtualisation and web hosting – update

I wrote recently about my efforts to find a cheap VPS host. Recently I’ve come across http://www.cloudorado.com/ which aims to make this process easier. It looks pretty good, but doesn’t seem to help much with the really small case – there’s no AWS Micro EC2 instances, for example.

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Developing in a Linux Virtual Machine on Windows

Sadly for this post, but luckily for the rest of us, VMWare have now released version 5 of the Player software. Everything seems to work as before and most functionality appears in the same place, but the screenshots are now out-of-date. I like Windows. I know my way around it, I’ve tried the alternatives and I […]

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Migration – Further Progress

Part1: http://blog.simpleigh.com/2012/06/virtualisation/ Part 2: http://blog.simpleigh.com/2012/06/migration-aches-and-pains/ Now my diary is settling in on its new server, I thought I’d add a couple of thoughts: It now runs far faster, feeling much more snappy and responsive. No other users are competing for server resources, and the server’s a lot nearer (Ireland rather than the US). NameCheap have […]

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Migration: Aches and Pains

I recently migrated my diary to a new server, and was amused by some of the problems I faced doing so. Deploying PHP applications should be a simple affair – set up the database, upload the code – but moving to a newer version of the language brought many problems. PHP now bothers to check […]

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Compression

A link recently bubbled up the frontpage of Hacker News, and I found myself rather curious to find out more. The headline rather proudly proclaimed: “RJSON: compress JSON to JSON”. JSON is a useful and simple way of transmitting data between machines on the Internet, and is commonly-used by many dynamic websites today (see Wiki […]

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Virtualisation and web hosting

I’ve been gradually starting to migrate bits of this site over to a VPS (Virtual Private Server) hosted on Amazon’s AWS. I’d originally come across the concept of a VPS at a previous job which had been offered a Slicehost instance for test purposes. While I’d experimented with Ubuntu on the desktop before, and had used a Linux […]

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Dvorak – settled in

Current wpm: 98. I’ve been enjoying trying to get my particular flavour of Dvorak working on Linux, and will post more details of how it’s going in the near future…

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Dvorak Day n

Current wpm: 56 (up from 20). Starting to get to grips with things now. I wrote out all the letters on sticky-labels and affixed them to the keyboard, which really did make an enormous difference. I no longer had to feel around for a key, or look at a separate diagram, but simply needed to […]

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Dvorak Day 4

Current wpm: 20 (stable from 20). A weekend away from the computer has prevented any further speed improvements. Maybe tomorrow will see a better result. I’m starting to remember where all the keys are, but am not at all fluent and have to make heavy use of the “backspace” key. On a side note, in […]

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Dvorak Day 3

Current wpm: 20 (up from 12). Did some serious practice today. Also made another keyboard layout so that I don’t have to re-learn all the punctuation. Will this process continue until all the keys are restored? Using the computer is very frustrating. Typing long passages is tiring, and it’s really annoying when doing something as […]

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Dvorak Day 2

Current wpm: 12 (down from 100 or so). Using the MS Keyboard Layout Creator, I’ve put together a UK Dvorak Variant. Am considering using speech recognition instead of typing, which is now tedious.

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The Dvorak Simplified Keyboard

I’m currently typing this very slowly having changed my keyboard layout to the Dvorak Simplified Keyboard. It’s proving quite slow-going, but will hopefully speed up my typing and reduce the strain on my wrists. Next report to follow.

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It’s OK, the software knows best

I find the attitude of some software developers ridiculously arrogant. They all think that they know best. They know the best algorithms, they write in the best language, and above all, they make the best decisions. Sometimes, however, I’m not so sure. Today I decided to clear out the small toolbar which acts as a […]

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