Docs / Safe Mode
| Level | Blocks | Use it when |
|---|---|---|
| Off | Nothing | Day-to-day editing. |
| Images | Writes inside opened CBM disk images | You're browsing a curated D64 collection and don't want to accidentally save into them. |
| Remote | Writes to the C64U over FTP | Demo'ing the device, presenting at a workshop, or browsing a friend's setup. |
| Images and Remote | Both of the above | Strong combination for read-only sessions. |
| Everything | Also blocks writes to the local PC filesystem | Looking only - no edits anywhere. Useful when handing the keyboard to someone else. |
What "blocked" looks like
Operations that would write are stopped before any change is made. You'll get a notification ("Blocked by Safe Mode - level: Remote"), the source pane stays untouched, and the destination is unchanged. There is no half-applied state.
What's not Safe Mode's job
Safe Mode does not prevent destructive operations on the C64 itself - for instance, a PRG you launch can still trash the device's RAM or write to a mounted disk via the Ultimate's drive emulation. It only governs the host (your PC) initiating writes through this app.