Lew's blog

Recently, for a variety of reasons, I got interested in how containers work in Linux. While my systems came with a version of the LXC container tools, I hadn't used containers for anything. But, a use-case appeared, and it piqued my interest. So I looked at containers and concluded that, if I were to use them, I would have to understand them first. And so, down the rabbit hole, I've gone.

My partner recently asked if I could receive a FAX for her. Sadly, I had to tell her that, while I can send faxes, I couldn't easily receive them. I do have a multifunction printer with FAX capability, but I have not designed my "Receptionist" dialplan to handle incoming faxes. And so, admitting that failing, I skulked back to my cave, and did some research.

With the telephony hardware installed and configured, and Asterisk in place, I found myself at the point where I could turn to my favourite topic: the software. And, even at the simplest, I had a lot of software to keep me busy. Luckily enough, I had the time.

Back in 2016, a question came up in one of the groups as to how you would code a pipeline in C. The requestor wanted C code equivalent to the shell pipeline

echo "Hello World" | tr "a-z" "A-Z" | sort | rev

Since I hadn't actually attempted before to write such a pipeline in C, I gave it a try. I came up with a couple of variations, which I never posted back to the newsgroup.

Recently, another question reminded me of my code. So, rather than let it moulder in my collection of coding bits, I post it here as a reference: