Aug
16
Creating an XKPasswd 2 OS X Service with Automator
Filed Under System Administration, Computers & Tech on August 16, 2014 | 4 Comments
It’s going to take me a few months to re-write the www.xkpasswd.net site so it uses the new XKPasswd 2 perl module. In the mean-time, thanks to the magic of Automator an OSX Services, Mac users can integrate XKPasswd 2 right into their OS with out very much effort at all.
This blog post is intended as a follow-on post to my earlier XKPasswd 2 beginners guide. This post assumes you have followed the installation instructions in the beginner’s guide to install the XKPasswd 2 module, that you followed along with that post and created a script that generates passwords in a format of your choice, and that you have tested that script to be sure it works. In this post I’ll be using the final example script from the beginner’s guide as my pre-written script.
Aug
16
XKPasswd 2 – An Absolute Beginner’s Guide
Filed Under Software Development, Computers & Tech on | 2 Comments
I’ve just released version two of the XKPasswd perl module, the module that powers the www.xkpasswd.net website. At the moment, only the module has been updated, not the website. It’s going to take me a few months to make all the changes I want to on that site. In the mean time you, can use the module directly. The prerequisites are that you have a computer with Perl and GIT installed, and a plain text editor (no difficult on Linux or Mac).
Jul
19
TTT Part 19 of n – Text Searches
Filed Under Computers & Tech, System Administration on July 19, 2014 | 1 Comment
In the previous two instalments (17 & 18) of this series we learned how to represent patters with regular expressions, or, to be more specific, with POSIX Extended Regular Expression (or EREs). We used the egrep
command to test our regular expressions, but we didn’t discus the command itself in detail. Now that we understand regular expressions, it’s time to take a closer look at both egrep
, and it’s older brother grep
, both commands for filtering and searching text.
May
10
TTT Part 18 of n – More REs
Filed Under Computers & Tech, System Administration on May 10, 2014 | 4 Comments
In the previous instalment we introduced the concept of Regular Expressions, and started to learn the POSIX ERE regular expression language, noting that POSIX ERE is a sub-set of the very commonly used Per Compatible Regular Expression (PCRE) language.
In this instalment we’ll learn more POSIX ERE syntax, and have a look at some examples of REs in GUI apps.
Apr
27
TTT Part 17 of n – Regular Expressions
Filed Under System Administration, Computers & Tech on April 27, 2014 | 5 Comments
This instalment is the start of a series of instalments relating to searching from the command line. Searching is all about patterns, and that means getting to grips with Regular Expressions (also called RegExps, RegExes or REs for short). Regular Expressions are languages for representing patterns, and are used throughout IT, not just on the command line. While this series focuses on the Terminal, an understanding of regular expressions will be helpful in many other places, from programming languages to GUI apps like programming editors, search utilities or file re-namers. It’s going to take us two instalments to properly describe regular expressions, but when we’re done we’ll have gained a very useful skill.
Feb
8
TTT Part 16 of n – Crossing the Streams
Filed Under System Administration, Computers & Tech on February 8, 2014 | 2 Comments
In the previous instalment we introduced the concepts of streams, and looked at how every process has references to three streams as part of their environment – STDIN
, STDOUT
& STDERR
. We went on to introduce the concept of operators that manipulate these streams, and we focused on the so-called ‘pipe’ operator which connects STDOUT
in one process to STDIN
in another, allowing commands to be chained together to perform more complex tasks. We mentioned the existence of operators for connecting streams to files, and the possibility of streams being merged together, but didn’t go into any detail. Well, that’s what we’ll be doing in this instalment.
Feb
2
TTT Part 15 of n – ‘Plumbing’
Filed Under System Administration, Computers & Tech on February 2, 2014 | 2 Comments
Right back in the very first instalment we described the Unix philosophy as being Lego-like, that is, having lots of simply commands that do one thing well, and then assembling them together to do something really powerful. So far, we’ve only been working with a single command at a time, but that changes with this instalment. We’ll be introducing the concept of streams, which can be used to connect commands and files together.
Jan
11
TTT Part 14 of n – Aliases & Prompts
Filed Under Computers & Tech, System Administration on January 11, 2014 | 1 Comment
In the previous instalment we looked at how to make permanent changes to our environment. We made a permanent change to the PATH
environment variable to demonstrate how it’s done (by editing ~/.bash_profile
on a Mac, or ~/.bashrc
on Linux). In this instalment we’ll look at two other kinds of environment changes you may wish to make by editing these files – specifically, aliases, and custom prompts.
Dec
21
TTT Part 13 of n – PATH
Filed Under System Administration, Computers & Tech on December 21, 2013 | 6 Comments
In the previous instalment we introduced the concept of the command shell environment, and we looked in detail at how shell and environment variables work. In this instalment we’ll focus on probably the single most important environment variable, PATH
. We’ll look at what it does, how it’s initialised, and, in the process, we’ll learn how to make persistent customisations to our shell environment.
Dec
14
TTT Part 12 of n – the Environment
Filed Under System Administration, Computers & Tech on December 14, 2013 | 2 Comments
Given the times we live in, the word ‘environment’ probably invokes images of polar bears and melting ice, but the Al Gore definition of the word ‘environment’ is a relatively recent narrow definition of a much broader word. The first definition of the work in the OS X dictionary is:
The surroundings or conditions in which a person, animal, or plant lives or operates
In this instalment we’ll introduce a digital extension of this concept – the digital conditions within which a process exists, and specifically, in which a BASH command shell exists. Although this might sound like a simple topic, there’s actually a lot to cover, so we’ll be spreading it out over a few instalments.