Page 1 of 1
When did OPEN_IN start working on Directory Devices?
Posted: Thu May 06, 2021 10:11 am
by NormanDunbar
I might be going mad (going????) but I'm sure that OPEN_IN #3,'ram1_' used to barf but it now works under SMSQ (on QPC at least) and I was wondering how long, has this been going on. (I hear a song!). In addition to successfully opening the device, it does also allow me to read the directory in 64 but chunks as I would have done using OPEN_DIR.
I don't recall seeing this documented anywhere, but having typed that, someone will, as usually, point me at an obvious place where it is documented!
Cheers,
Norm.
Re: When did OPEN_IN start working on Directory Devices?
Posted: Thu May 06, 2021 10:39 am
by tofro
NormanDunbar wrote:I might be going mad (going????) but I'm sure that OPEN_IN #3,'ram1_' used to barf but it now works under SMSQ (on QPC at least) and I was wondering how long, has this been going on. (I hear a song!). In addition to successfully opening the device, it does also allow me to read the directory in 64 but chunks as I would have done using OPEN_DIR.
I don't recall seeing this documented anywhere, but having typed that, someone will, as usually, point me at an obvious place where it is documented!
I'm not sure it's documented somewhere, but that's how directories work in QDOS? It would have to be explicitly caught and forbidden in order to not work. The same also seems to work with Minerva in Q-Emulator.
Re: When did OPEN_IN start working on Directory Devices?
Posted: Thu May 06, 2021 11:30 am
by dilwyn
Ever since level 2 drivers (directories) came into being I think.
On a level 2 system, try COPY WIN1_ TO SCR for example, to see the directory. Works with any level 2 device IIRC.
The "root" (or whatever is the correct term for a null name file on a drive) used to be usable as a file on older level 1 disk systems. It was sometimes used as an "invisible" file in some protected software, such as older versions of the Sinclair Software Production Kit.
Re: When did OPEN_IN start working on Directory Devices?
Posted: Thu May 06, 2021 11:31 am
by pjw
Same goes for fop_in(<devn><dir>) so, clearly, its a feature.
Re: When did OPEN_IN start working on Directory Devices?
Posted: Thu May 06, 2021 3:42 pm
by NormanDunbar
Hi Dilwyn,
dilwyn wrote:Ever since level 2 drivers (directories) came into being I think.
Good to see I've been keeping up with changes then!
dilwyn wrote:The "root" or whatever is the correct term for a null name ... was sometimes used as an "invisible" file in some protected software...
I remember that. Never used it myself but I
think you had to make the first character of the file name CHR$(0) and the dir command wouldn't list it.
Thanks.
Cheers,
Norm.