cowsayis an extremly fun and super easy to use command. Just put whatever you want as an argument after the command and you’ll be greated with an ASCII cow and a speech bubble saying it. This probably isn’t installed by default, so fire up your favorite package manager and install it!
I think it is now……week three of working from home. Rather than get into the nitty gritty of some standard UNIX command, I thought I’d take this week to introduce you to a few fun commands. Some of these are non-standard, and by that I mean they are usually not available by default on your system. So you’ll have install it, sorry. They can be installed with any package manager, I can confirm at least with
brewfor macOS and
aptfor Ubuntu/Debian. Let’s start this off with a funny little command called
Boy oh boy, where to begin with
grep. This one took me down a rabbit hole.
grepis one of those tools that I feel has always been there; like with
cd. It is a command I’ve come to rely on for almost anything I do on the command line. I will say this,
grepis powerful, like SUPER powerful. It’s so vast and complex that people have written multiple books about it. So before we dive in, remember that this is an overview. It won’t cover everything, because I cant. But I hope to give you some building blocks to which you can use to build greater things.
What a great name for a tool. Funny enough, there is a
dogcommand, but it’s not installed by default. The original
catcame with Unix version 1 in November 1971, and it replaced an older command called
pr. Believe it or not, chances are, the
prcommand is on your machine today! That’s a new one on me. The
prcommand has a different output format than
cat, making it a bit “prettier” because it offers a pagination filter. Anyway, back to
chmod, this is another program that has stood the test of time…Unix time ba dum tsh. This was also another command that was released with Unix 1, and the GNU version was released as part of Fileutils in October 1992. The
chowncommand stand for change owner. As you may have guessed, it allows one to change the owner of a file or directory, and allows you to change the group as well.
This is one of the oldest commands as it has been around since the first version of Unix that was released in 1971. The GNU version was written by David MacKenzie, the same author as
tail, and many others that I haven’t covered yet.
chmodstands for change mode. What some may consider to be file permissions were considered modes, and are still referenced as such.
Like all great Unix commands,
tophas a meaning behind its name. It stands for Table Of Processes. Not surprising as it shows a wealth of information running about the system. If you’re running a Linux machine, or macOS (or some BSD variant),
topis an extremely useful program. It is a task manager, err..well, more of a system monitor, but has some task manager like properties. The original program was first released in 1984 by William LeFebvre for Unix.
Going to end this week with the last DNS lookup tools released with BIND9. I’m sure there are other DNS lookup tools, and I know the Internet Systems Consortium has various other tools for you to use. Today we’re looking at
dig, the first DNS lookup utility I ever used back in the day. Had now idea how it worked, kind of just copied and pasted code, but thought it was so cool to get an IP address of a website.