This tip probably seems a bit stupid, but I have always found very useful. If we want to replace a string in a file with another string, we can do it easily using Perl:

perl -p -i -e 's|old_string|new_string|' file.xml

Of course, if we need to apply it to several files we can use a wildcard character.

The beta version of the latest Ubuntu, Hardy Heron 8.04, has been released. The official release will be on April 24th 2008.

Link | Ubuntu releases

Paolo Maldini, as know as Il Capitano said goodbye to the top flight of football after a thrilling match against Arsenal FC. Maldini has been one of the best defenders in the world, and after 24 seasons playing at AC Milan, Maldini will retire from the fields. The rossonero team has said that the number three that Paolo Maldini has used since his debut will not be assigned to any player ever again after his retirement, except his children Christian and Daniel, if someday they would play in the first team.

One use of the lower-case Greek letter λ is a branch of mathematical logic called Lambda Calculus. It’s a formal system designed to research function definition, function application and recursion. Throughout the years, λ has been seen on many logos related with the functional programming. For example, the MIT Scheme’s logo represents a recursive shield with lambda:

We can see lambda on the functional programming language Haskell’s logo. Apart from lambda, we can see five other mathematical symbols, representing the Haskell’s functionality. These are their respective meanings:

-The right arrow (→): Transformation
-The universal quantification (∀): For all
-The double angle (≫): Free from disorder
-The double right arrow (⇒): Generality
-The double colon (::): Exactitude

A scheme-to-C compiler called Chicken has a logo that represents a lambda inside a hen silhouette.

CL-HTTP (Common Lisp Hypermedia Server) has a lambda symbol on its logo too.

More information | Xahlee

The first century starts at 0001-01-01 00:00:00 AD, although they did not know it at the time. This definition applies to all Gregorian calendar countries. There is no century number 0, you go from -1 to 1. If you disagree with this, please write your complaint to: Pope, Cathedral Saint-Peter of Roma, Vatican.

Seen on PostgreSQL Documentation

Many people speak about the future of web applications, but I would like to stop and comment on the present. I have been observing a curious phenomenon throughout the recent years. I have seen a backwards movement as far as the way of the social communications on the Internet are concerned. For example, I can spot similarities between Twitter and the IRC, which is still in use, but not like few years ago. The first difference that I have noticed is the transmission time. The communication by IRC is synchronous, whilst the communication on Twitter is unsynchronous.

An unsynchronous communication has some advantages. The main advantage is probably the null intrusivity. An unsynchronous method is not intrusive. We can find an analogous example on the use of phone or email. When someone phones you, you have to stop what you are doing in order to answer the call. On the other hand, if someone sends you an email you can read it whenever you like. Obviously the priority plays an important role, for example if you have something urgent to say, an unsynchronous method is not the most appropriate way.

Another advantage of an unsynchronous method is the possibility of reading (or listening, or watching) a document wherever and whenever you like. It is not possible to do this using a synchronous method.

In my opinion, this regressive trend is an intelligent movement.

Thierry Henry’s amazing goal against Celtic Glasgow.