RISC for Dogs (2)

Figure 1:  I think it’s time for a break.

This is continued from page 1 of the post ...

I glossed over some items. I always hate it when other authors “gloss the details” – don’t you? So, you may wonder how I managed to instantiate the task window, into which I typed the various commands. In the lower right corner of the desktop is a big raspberry graphic (on the Pi version of the OS). Pressing the middle mouse button while the cursor is positioned over the raspberry produces a menu with a “task window” item. Clicking that item produces the task window.

You may wonder how I unzipped the SerialUSB file. I double-clicked it, and the OS produced a second window containing the decompressed zip-file contents. This is a virtual, read only directory window, and so the contents must be copied to a real directory in many cases (maybe not – if one is just running a program). In my case, I selected all of the items in the zip folder by pressing the middle mouse button, and then selecting the “Select all” item on the menu that appeared. I had already created a subdirectory for the files, and so I just dragged the selected zip folder files over to the new directory I’d previously created. How did I create that directory? I could have done it on the command line in a task window, but instead I (again) pressed the middle mouse button while positioned inside of the parent window, and selected the “New directory” item from the menu that appeared.

I mentioned on page one that, on RISCOS, an “application” is a directory name prefixed with the pling, like:


But, I glossed over the details.  Double clicking the directory runs the program.  So, how does one access the files inside?  It’s a trick: hold down the shift key while double clicking the directory.  A directory windows will open, with all of the content files of the “application”.  These things are pretty intuitive, and without my going on-and-on about them, a reader would figure it out him/herself in short order.  There’s another trick involving the shift key.  When a file is dragged from one folder to the next, it is copied to the second folder.  But, if the shift key is held down as the content is dragged to the second window, that content will be moved to the second window.

Ah. The devil’s in the details, but we gotta have em.

The OS has a zillion file types (like mime types for most OS’s).   Some of these are very specific (for instance, to a particular vendor’s word processor).  I think that a small problem occurs because these file types are not in the mainstream.  As an example:

The NavSat program I tried to use came down to the machine as a “data” file type.  This is what’s assigned when the OS doesn’t know how to type the file.  So, the archiver wouldn’t unzip it.  I changed the file type (using the middle mouse button, and selecting “Set file type“) – but it was still a no-go.  So, I downloaded the file to a Linux box, and repackaged the contents to a tarball, since the zip file was extracted OK on Linux.   That turned out to be a bad move.

Sure, the tarball was extracted easily on RISCOS.  But – every single file in the archive was typed to “data” – because Linux doesn’t know hoot about this nice little operating system.  That’s OK, because I got to learn about what files are typed with what type in my newly adopted OS.  I manually typed all the files in the archive (with a middle click, “Set file type” on each file).  I think RISCOS keeps more metadata on files than Linux (or any other OS).  So, this has to be considered when copying.

Here’s how I typed the files:

  • Files OLED, OLED_0-06, PiSPI were modules, so I set the file type to “Module
  • All files with the word “log” in them I set to type text – “FFF”
  • I set the type of the binary (app) files to “Absolute”
  • Most of the rest of the files were “obey” files, and so I typed them to “Obey”
  •        And finally, there were a number of files that really were “Data” files.

Again, take this list with a grain of salt.  I could have one or more of the types wrong.  Still learning.  An “obey” file is a command file (like a script).  It can use the BBC BASIC language for “scripting” the RISC way.

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RISCOS is a product of Castle Technology Limited (“Castle”) and its licensors at:
http://www.castle-technology.co.uk/  This author and site are not affiliated with them in any way.

Note: This author and site is not affiliated with the Raspberry Pi in any way. For information about those projects visit  http://www.raspberrypi.org “Raspberry Pi” is a trademark of the Raspberry Pi Foundation.