The CBM DOS can write “relative data” onto disk, based on individual records. The advantage is that all space is allocated once and then randomly accessed if and when it’s needed – much like the tracks on a CD. This approach is different from sequential files, which have to read or write the whole file … Read more
Sequential files are files to which we can write arbitrary data and read it back later. We can even append data to the file later without having to re-write the whole file. This works with the Datasette (tape drive) as well as floppy drives. Here’s how to do it in CBM BASIC 7.0: Creating Sequential … Read more
The Commodore 1571 floppy drive powers up in compatibility mode and behaves just like a 1541 drive – unless a C128 is connected and sends it a fast serial transfer. They did this because otherwise the drive wouldn’t be compatible with the C64 and Plus/4. The C128 speaks to its attached disk drive when we … Read more
Sometimes you may want to know how fast your fans are spinning, more as a “number value” rather than a “noise value”. While you can hear when your Mac in front of you is working hard, it’s impossible to tell how fast those fans are spinning when you’re miles away from your Mac in a … Read more
System Integrity Protection was introduced in El Capitan to add another layer of security to OS X. The system prevents the root user from doing things that are potentially harmful. Apple did this because any app at any time may ask for the administrator password and execute commands with elevated permissions, which is a big … Read more