"cpp" entries

Learn a C-style language

Improve your odds with the lingua franca of computing.

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You have a lot of choices when you’re picking a programming language to learn. If you look around the web development world, you’ll see a lot of JavaScript. At universities and high schools, you’ll often find Python used as a teaching language. If you go to conferences with language theorists, like Strange Loop, you’ll hear a lot about functional languages, such as Haskell, Scala, and Erlang. This level of choice is good: many languages mean that the overall state of the field is continually evolving, and coming up with new solutions. That choice also leads to a certain amount of confusion regarding what you should learn. It’s not possible to learn every language out there, even if you wanted to. Depending on the area you’re in, the choice of language may be made for you. For the overall health of your career, and to provide you the widest range of future opportunities, the single most useful language-related thing you can do is learn a C-style language.

A boring old C-style language just like millions of developers learned before you, going back to the 1980s and earlier. It’s not flashy, it’s usually not cutting edge, but it is smart. Even if you don’t stick with it, or program in it on a daily basis, having a C-style language in your repertoire is a no-brainer if you want to be taken seriously as a developer.
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Where apps end and the system begins

Exploring the system calls and control flow that underpin high-level languages.

Editor’s note: Sometimes we can forget how important it is to truly understand how a system works, and how the nuts and bolts affect our everyday activities. Marty Kalin asks us to dive a little deeper and strengthen our computational thinking abilities.

It’s clear that applications need system resources to execute: a processor, memory, and usually I/O devices such as the keyboard and screen. It’s less clear how applications gain access to these shared resources, which are under operating system (OS) control. The OS, like any good manager, is efficient and unobtrusive as it handles resource requests from applications. Let’s take a look at how applications interact with the OS, in both routine and dramatic fashion.

Consider what happens when a print statement executes. Here’s a Ruby example:

puts 'Hello, world!'

The Ruby puts statement wraps a call to a high-level I/O function in the standard C library (in this case, printf), which acts as the interface between resource-requesting applications and resource-granting OS routines. In this example, the screen is the requested resource. The standard library interacts seamlessly with the OS, which also is written in C with some assembly language. The library function printf is high-level because, as the f in the name indicates, the function can format the bytes to be written as integers, floating-point values, and character strings such as Hello, world!. In systems-speak, the Ruby application and the C library function execute in user space, which does not bestow the rights and privileges needed to control system resources such as the screen.

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