The C64 - Disc operations / BASIC - How to delete files? (2024)

Hi all,

I'm really having a blast programming BASIC on my "new" C64.
I've already stored many programs on the internal TheC64 disk and my son also has written many iterations of groundbreaking software (e.g. a ballon flies from left to right) and saved it to that disk.

Long story short...
How do I "delete/scratch" a program from a disk in this emulation environment?

I've tried this already:

OPEN 15,8,15,"S0:<filename>":CLOSE 1

But it is not working. My guess is, that I'm doing something wron with the device numbers S0 and so on.

I'm done with my experimenting and can't really figure it out.
I'm old... so i don't have much time left haha.
Has anyone of you tried this already?

Thanks very much in advance
Atom

BigFairy321 wrote:Haven't tried what your trying, but have you tried using a file copier like fast hack'em ?

Ooh... that sounds interesting.
I'll try that soon!

try this please:

OPEN1,8,15,"S:FILENAME"
CLOSE1

(p.s. if it wasn't a typo in your post: there's a 1 at the end of your line, it should be 15. it's the first number you need to close, so the command gets finished.)

RetroLynx wrote:try this please:

OPEN1,8,15,"S:FILENAME"
CLOSE1

(p.s. if it wasn't a typo in your post: there's a 1 at the end of your line, it should be 15. it's the first number you need to close, so the command gets finished.)

Yes!
This works - BUT you have to restart the Emulator to see the change on the disc.

I think you do not have to reboot the C64 but that you have to re-load the directory like so:

LOAD "$",8

And then list the directory with:

LIST

If you delete something from the disk then it is gone. However, the old directory list of that floppy disk is still in the 64 kB of internal memory of the C64. You'll have to force the C64 to re-read the contents of the floppy. For people like me that got used to computers when they had a hard disk, from which you can read directly, this takes some getting used to. Gotta love the way the C64 works. Fascinating.

Atombender wrote:

RetroLynx wrote:try this please:

OPEN1,8,15,"S:FILENAME"
CLOSE1

(p.s. if it wasn't a typo in your post: there's a 1 at the end of your line, it should be 15. it's the first number you need to close, so the command gets finished.)

Yes!
This works - BUT you have to restart the Emulator to see the change on the disc.

Ok, here is what works for me (The C64, classic mode, PAL 50, Firmware 1.3.2)

Load the contents of disc:

LOAD "$",8

Show files:

LIST

Delete desired file:

OPEN 15,8,15,"S:PROGRAMNAME":CLOSE15

Load contents again with

LOAD "$",8

Check with

LIST

Done

Thanks for your contributions (still not sure why I need the 15 or will 1 do as well?)
Atom

Atombender wrote:[...] (still not sure why I need the 15 or will 1 do as well?)

Many people use "15". But AFAIK the first "15" is the descriptor of the channel that you opened. That descriptor might as well be "1", many people do.

BTW: if you want to edit the contents of a disk you can also download and attach an image file of the 'Final Cartrigde III' (link). See what I wrote about that in this topic:

It's disk utility however is where it still shines today. I use it to rename files, re-sort the dir list etc. It's quirky because it sometimes appears to not have saved my changes though...

I'm going to strongly suggest getting a ROM with a DOS wedge, either JiffyDOS or Epyx FastLoad.

You should be able to fire up the TheC64 with an Epyx FastLoad CRT installed like any other game - but EFL should drop you to the BASIC prompt, rather than a game title.

Then loading programs is as simple as typing

/filename

and you can issue disk commands with the @, so:

@s0:filename

and $ gets a directory

I never use my Commodores without a Fast loader, just for the convenience if not the speed.

TomXP411 wrote:I'm going to strongly suggest getting a ROM with a DOS wedge, either JiffyDOS or Epyx FastLoad.

Y...

I never use my Commodores without a Fast loader, just for the convenience if not the speed.

I've actually owned that cartridge but I forgot - I'll download it soon.
Thanks for the memory leak fix