Scala, Java, Unix, MacOS tutorials (page 385)

According to a report on the New York Times website, a new study conducted by Harris Interactive for CareerBuilder.com showed that "45 percent of employers questioned are using social networks to screen job candidates", and "35 percent of employers decided not to offer a job to a candidate based on the content uncovered on a social networking site".

Oracle has won approval from the U.S. government for their purchase of Sun (formerly Sun Microsystems). The deal is still subject to approval by the European Commission(EU). Oracle said they expect the deal to close by August 31 (2009).

I don't own stock in either company, but I'm interested to see what happens to many different Sun products, including:

As a few thousand people saw earlier this morning, Day 3 of the conversion to Drupal was filled with a little comedy. First, I ran into a MySQL "can't create/write to file" error message caused by not having the open-files-limit cranked up high enough.

I don't know how big of a deal it is yet, but as I learn more about Drupal and security, I just tightened down access to the Drupal cron.php script on this site.

One thing Drupal does is make a "cron" script available off of your root URL, and by default that script is made publicly available. I don't know exactly how this works yet (other than knowing that it fires off several Drupal cleanup tasks), but I really don't want to make that URL publicly available, so after digging around I found this nice Apache configuration solution here:

Mac question: Something just went wrong, and I need to start my Mac (or iMac) in safe mode, or something like safe mode? Can this be done on a Mac?

Answer: Yes, Mac computers support a "safe mode" boot process. Here are the steps needed to start your Mac/iMac in safe mode:

I was curious about how the "smudge resistant" feature of the new iPhone 3GS works, and after digging around a little bit, I learned that this capability is referred to as oleophobic.

Then, after a little more digging around, I found a nice article by Bill Nye (the science guy), who describes how this oleophobic iPhone feature works. Here's a brief excerpt from his article:

One of my beliefs regarding you and your career in the software industry is that you need to understand your strengths and weaknesses, and improve both.

I'm sure this will sound strange to some people who know me, but I was happy to stumble on several Eclipse user interface design documents yesterday, including their UI Best Practices, User Interface Guidelines, and Top Ten Lists Working Page documents.

I ran across some Java source code today that I thought I should share. This code demonstrates how to use the Java WeakHashMap class, which can serve as a nice cache some times. I particularly like how this class responds to available memory and the Java garbage collection system.

Let me share the Java source code here first, and then I'll provide a description of how it works:

One of the great things about Function Point Analysis (FPA) is that it can be a terrific validator of the work you’re doing as a business analyst. For example, here’s one of the guidelines I came up with after I learned about FPA:

If you can’t count the Function Points when you’re about to start developing a software project, you’re about to enter a world of hurt.

Perl CSV column data extraction FAQ: Can you share an example of how to extract one or more columns from a Perl CSV file or other similarly-formatted flat text file?

Perl is a terrific language for text processing, but several readers have written wondering about how to extract columns of data from text files with Perl. For instance, when you have a text database that looks like this:

Perl shell environment variables FAQ: How can I access Unix shell environment variables from a Perl script?

One of the great features of the Perl language is it's support of associative arrays. Unlike normal arrays, whose subscripts can only be integers, the subscripts of associative arrays are text strings. This may not sound like much yet, but with associative arrays (or hashes as they're now called) we can create fairly complex data structures with Perl.

In Part 1 of this series, we provided some background information about cookies, discussing the problem of state maintenance in web applications. We discussed how cookies can help solve this problem, and outlined the drawbacks and limitations of cookies. We even discussed a few examples of how you might use cookies in a customizable web site or e-commerce site.

Perl pipeline FAQ: How can I read output from a shell command pipeline (pipe) in a Perl script?

One of the great things about Perl is that it's very easy to run operating system commands, and read the output of those commands. Perl makes this process very easy and natural - it's just like reading data from a file. In this article we'll demonstrate the process of running external commands from within Perl, and then reading the output of those commands.

For many Unix users, Perl has replaced the Bourne shell, C shell, and Korn shell as a preferred programming language for many scripting duties and short programs.

Used as a scripting language, Perl programs often require you to prompt the user to enter some type of input. I've found that instead of writing separate "prompting" code in each of my Perl scripts, it's easier to create one prompting routine that can be used in almost all Perl programs.

Perl CGI environment variables: How can I print all of the Perl CGI environment variables? I'd like to see what CGI environment variables are available, and what their values are.

Somewhere in my history of working with Perl and CGI programs, I decided I needed a program that would simply print all of the CGI environment variables that my Perl programs were aware of. I can't remember if it was curiosity or what, but I decided that I needed a CGI program that did nothing else but print the environment variables it knew of.

Perl modules FAQ: I need to use a Perl module, but it isn't installed in the standard/default location, what can I do?

When you have root access to a Unix server, it's pretty easy to install Perl modules in their proper locations, and forget about them. But if you don't have root access and you need to install your Perl modules in non-standard directories, how will you get your programs to find your modules?

Ouch, I have no idea what happened over at CentOS, but it doesn't sound good. Eight of their developers signed (electronically) an "open letter" to Lance Davis (currently display on the centos.org home page). To say the least, it looks like there have been some communication problems on the team, which these developers have made very clear in both their open letter and in a separate statement of facts about their communication problems.