Linux Fu: Gum Up Your Script

We often write quick bash scripts and judging by the comments, half of us use bash or a similar shell to pop out quick, useful scripts, and half of us think that’s an abomination, and you should only use bash for your command line and resort to something more like a traditional language to do anything else. If you’re in the former camp, you’re probably cursing your allegiance when you need to make your bash scripts more interactive.

Gum can help. It’s a utility that can handle your script input and output with a little flair while requiring almost no effort on your part.

The command looks simple, but it has twelve subcommands, each with myriad options. But you can break down the functions into a few simple categories. The input commands let you prompt for a line of input or a bunch of lines of input. You can also create a pick list or a yes/no type of prompt. There’s also a file picker and a filter, sort of like fzf.

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PyScript: Python In The Web Browser

A chainsaw can make short work of clearing out the back forty. It can also make a good horror movie. So while some people will say we don’t need another tool to allow more malicious scripting in the browser, we also know that, like any tool, you can use it or abuse it. That tool? PyScript, which is, of course, Python in the browser.

The tool is in the early experimental phase, so the project doesn’t suggest using it in a production environment yet. However, if it works well, the promise is not just that you can write browser-based applications in Python — you’ll have a handy way to reuse existing Python code and even be able to run the same code on the browser that currently runs on the server. This has a lot of implications for improved client/server applications, or cases where you want to be able to run against a local backend when disconnected and a remote backend when you do have a connection. Of course, you can interoperate with JavaScript, too.

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BASH Template Promises Safer Scripts

Many bash scripts start out as something quick and dirty but then become so useful that they live for years, indeed sometimes seeing more use than our traditional programs. Now that you can even run bash well under Windows (although, you’ve always been able to run it there if you tried), there are even more opportunities for your five-minute bash script to proliferate. [Maciej] decided he was tired of always having to patch up his quick and dirty scripts to be more robust, so he created (and shared) his boilerplate template for scripts.

Probably most of us have at least some basic template we start with, even if it just our last script project. What’s nice about [Maciej’s] template is that he documents what’s going on with each part of it. It is also relatively short without a lot of excess stuff. Of course, you’ll probably customize it, but it is a great place to start.

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Does PHP Have A Future, Or Are Twenty Five Years Enough?

In June, 1995, Rasmus Lerdorf made an announcement on a Usenet group. You can still read it.

Today, twenty five years on, PHP is about as ubiquitous as it could possibly have become. I’d be willing to bet that for the majority of readers of this article, their first forays into web programming involved PHP.

Announcing the Personal Home Page Tools (PHP Tools) version 1.0.

These tools are a set of small tight cgi binaries written in C.

But no matter what rich history and wide userbase PHP holds, that’s no justification for its use in a landscape that is rapidly evolving. Whilst PHP will inevitably be around for years to come in existing applications, does it have a future in new sites?

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Linux Fu: Shell Scripts In C, C++, And Others

At first glance, it might not seem to make sense to write shell scripts in C/C++. After all, the whole point to a shell script is to knock out something quick and dirty. However, there are cases where you might want to write a quick C program to do something that would be hard to do in a traditional scripting language, perhaps you have a library that makes the job easier, or maybe you just know C and can knock it out faster.

While it is true that C generates executables, so there’s no need for a script, usually, the setup to build an executable is not what you want to spend your time on when you are just trying to get something done. In addition, scripts are largely portable. But sending an executable to someone else is fairly risky — but your in luck because C shell scripts can be shared as… well, as scripts. One option is to use a C interpreter like Cling. This is especially common when you are using something like Jupyter notebook. However, it is another piece of software you need on the user’s system. It would be nice to not depend on anything other than the system C compiler which is most likely gcc.

Luckily, there are a few ways to do this and none of them are especially hard. Even if you don’t want to actually script in C, understanding how to get there can be illustrative.

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Add Scripting To Your C++ Programs With ChaiScript

If you are writing a program that has a technical user base, it is a nice touch to make the program scriptable. In fact, you might want to do the hard work in a programming language and then use your scripting language to build out features. In theory, this should be easy. There are plenty of embedded scripting libraries and they provide some way for your code to access script resources and for script resources to access selected host variables and functions. If you use C++, one of the easier ways to do this is with ChaiScript.

ChaiScript is BSD licensed and — assuming your compiler supports C++ 14 — it is as easy as including a header file and making a few calls. There are no special tools or libraries required. The code is portable between operating systems, including both 32-bit and 64-bit Windows. It is also threadsafe unless you turn that feature off.
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Scripting Language Rapidly Develops A Clock

In the past, you might very well have started programming in Basic. It wasn’t very powerful language and it was difficult to build big projects with, but it was simple to learn, easy to use, and the interpreter made it easy to try things out without a big investment of time. Today you are more likely to get started using something like an Arduino, but it is easy to miss the accessible language and immediate feedback when you are doing simple projects. Annex WiFi RDS (Rapid Development Suite) is a scripting language for the ESP8266 that isn’t quite Basic, but it shares a lot of the same attributes. One example project from [cicciocb] is a scrolling dot matrix LED clock.

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