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Email Analytics

During the past six months I've been drowning in email. I spend a large part of my day responding to email messages and filing incoming messages I consider important. Yet I'm falling behind and this affects the quality of my work: I sometimes delay responding to important messages. Followng Peter Drucker's dictum "If you can't measure it, you can't manage it", I decided to write a tool to analyze my incoming and outgoing email messages.

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Palindromic Palindrome Checking

Stan Kelly-Bootle's column in the April 2007 ACM Queue, titled Ode or Code? — Programmers Be Mused!, was as always very enjoyable. However, I found its ending, a C function that returns true when given a palindromic string (e.g. ABCCBA), anticlimactic. The function given is recursive; I was expecting it to be palindromic. How difficult can it be to write such a function?

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How to Embed Citations in Diagrams

Diagrams in scientific publications occasionally link to other elements of the publication, such as bibliographic or section references. Maintaining consistency between the citations in the diagram and the publication can be tricky, but a small Perl script can automate this process.

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Code Quality: The Open Source Perspective

My new book Code Quality: The Open Source Perspective got published, three years after I started writing it. The book owes more to open source software than any of the books dealing with Linux, PHP, Apache, Perl or any other book covering a specific technology.

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Java Makes Scripting Languages Irrelevant?

Simplicity does not precede complexity, but follows it.

— Alan J. Perlis

In computing we often solve a complex problem by adding another level of indirection. As an example, on Unix file systems an index node, or inode, data structure allows files to be allocated concurrently and sparsely, and yet still provide an efficient random access capability. When we want to customize large and complex systems or express fluid and rapidly changing requirements a common tool we employ is to add a scripting layer on top of the corresponding system. An early instance of this approach was employed in Dan Murphy's TECO editor developed on the DEC PDP-1 computer in 1962–63: its command language also doubled as an arcane (to put it politely) macro language.

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Measuring the Effect of Shared Objects

For the Code Quality book I am writing I wanted to measure the memory savings of shared libraries. On a lightly loaded web server these amounted to 80MB, on a more heavilly loaded shell access machine these ammounted to 300MB.

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Digital Data Makes Anything Possible

Once data becomes digital anything and everything becomes possible. Consider arranging the books on your bookshelf by the color of their bookcover.

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Computer Languages Form an Ecosystem

(This is a copy of an article I posted on slashdot on March 15th, in response to a discussion titled C Alive and Well Thanks to Portable.NET. Many posters argued that the C language is dead. I add my response here, because one month after its original slashdot submission, I am still getting web site hits from it.)

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Binary File Similarity Checking

How can one determine whether two binary files (for example, executable images) are somehow similar? I started writing a program to perform this task. Such a program could be useful for determing whether a vendor had included GNU Public License (GPL) code in a propriatary product, violating the GPL license. After writing about 20 lines, I realized that I needed an accurate definition of similarity than the vague "the two files contain a number of identical subsequences" I had in mind.

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