I noted in Slackware Diary that I had installed Free42 under Slackware. As I wrote in 2006 I fell in love with HP calculators and their RPN notation back in the 1970s, and still find the conventional algebraic notation rather awkward. I no longer carry a physical calulator, but I have Free42 installed on my phone and my tablet, and on my Windows systems. Now I also have it on Slackware. So I circled back to see if I could install in on Ubuntu.

The Ubuntu 20.04 repository includes free42-nologo and I installed it with sudo apt install free42-nologo. The installation ran OK. Like on Slackware no icon was created, but /usr/bin/free42bin did appear. Since /usr/bin/ is in $PATH, free42bin can be invoked from the command line. Unlike with Slackware and Windows, there is no free42dec. Invoking free42bin gave me an error message:

gmcdavid@Donegal:~$ free42bin &
[3] 213114
[2]   Done                    free42bin
gmcdavid@Donegal:~$ Gtk-Message: 10:17:03.320: Failed to load module "canberra-gtk-module"

However, the calculator did appear on my desktop and it worked, at least for simple calculations. Stackoverflow suggested

sudo apt-get install libcanberra-gtk-module

and now free42bin works just like it does on Slackware. I do not understand what happened to free42dec.

Ubuntu 22.04 get it right. sudo apt install free42-nologo installs both free42bin and free42dec, and both have icons to invoke them from the GUI.