I thank you for your reply, but I got the information I needed elsewhere. 
I didn't mention this before, as I thought nobody would respond.

On Sunday, June 24, 2018 at 7:45:26 AM UTC-4, John Rumm wrote:
> On 09/06/2018 00:21, Harry Potter wrote:
>
> > Hi!  I *still* need help opening files on a PET.  I want to port
my DirMenu program to the PET.
>
> Have a look about 2/3rs of the way down this:
>
> http://www.commodore.ca/download/commodore/Vice_PET_notes.txt
>
>
>
> --
> Cheers,
>
> John.
>
> /=================================================================\
> |          Internode Ltd -  http://www.internode.co.uk            |
> |-----------------------------------------------------------------|
> |        John Rumm - john(at)internode(dot)co(dot)uk              |
> \=================================================================/

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