phatcode.net / forum / view message

View Message

Plasma Fri Oct 4 2024 at 3:08 pm
strange

I think the problem may be a combination of QB/DOS. DOS will only put as many bytes in the read buffer as requested, so that itself shouldn't be an issue. But if DOS is reporting both the file size as 0 and also never EOF, it's probably screwing with some checks QB does to avoid a buffer overflow.

CLOCK$ device file in MS-DOS - Peter Swinkels (Thu Sep 19 2024 at 1:22 pm)

DOSBox does not implement CLOCK$ - Plasma (Mon Sep 23 2024 at 10:51 pm)
- A small QBasic program that can read from CLOCK$-> - Peter Swinkels (Tue Oct 1 2024 at 2:09 pm)
  - And here is a version written in C-> - Peter Swinkels (Fri Oct 11 2024 at 2:52 pm)
    - what value is fread returning? * - Plasma (Sun Oct 20 2024 at 9:31 pm)
      - Okay I figured it out. - Peter Swinkels (Thu Oct 24 2024 at 1:09 pm)
        maybe sizeof(struct ClockStr)? - Plasma (Thu Oct 24 2024 at 6:37 pm)
        Now why didn't I think of that? It works! * - Peter Swinkels (Fri Oct 25 2024 at 4:24 am)
        nice * - Plasma (Fri Oct 25 2024 at 10:51 am)
      - You mean what value of fread is returning?-> - Peter Swinkels (Thu Oct 24 2024 at 3:50 am)
      - You mean what value of fread is returning?-> - Peter Swinkels (Thu Oct 24 2024 at 3:50 am)
  - what was the issue - Plasma (Wed Oct 2 2024 at 11:09 am)
    - Not sure but-> - Peter Swinkels (Wed Oct 2 2024 at 3:29 pm)
      - Did some testing. - Peter Swinkels (Thu Oct 3 2024 at 1:18 pm)
        Maybe QB is letting you read past the end of the "file" - Plasma (Thu Oct 3 2024 at 6:53 pm)
        I did some more testing with some interesting results-> - Peter Swinkels (Fri Oct 4 2024 at 1:00 pm)
        strange - Plasma (Fri Oct 4 2024 at 3:08 pm)
        Some more tests: - Peter Swinkels (Sat Oct 5 2024 at 12:17 pm)
        Narrowed it down-> - Peter Swinkels (Sat Oct 5 2024 at 12:22 pm)
        even INPUT$(1, FileH) crashes? * - Plasma (Mon Oct 7 2024 at 9:54 am)
        Repeated uses of INPUT$ with very small buffer causes crashes-> - Peter Swinkels (Mon Oct 7 2024 at 1:00 pm)
        I think the actual INPUT$ buffer is internal - Plasma (Mon Oct 7 2024 at 4:51 pm)
        Here's a quick test I wrote in C-> - Peter Swinkels (Thu Oct 10 2024 at 1:42 pm)
        ftell-> - Peter Swinkels (Fri Oct 11 2024 at 2:58 pm)
        
        See-> - Peter Swinkels (Fri Oct 11 2024 at 2:53 pm)
        
        Well-> - Peter Swinkels (Sat Oct 5 2024 at 3:50 am)
- sec/100 ? - Peter Swinkels (Tue Oct 1 2024 at 1:58 pm)
  - Never mind. - Peter Swinkels (Tue Oct 1 2024 at 2:03 pm)
- I was using actual MS-DOS 6.22-> - Peter Swinkels (Tue Oct 1 2024 at 3:19 am)
  - I see - Plasma (Wed Oct 2 2024 at 11:00 am)
    - Ah I see, - Peter Swinkels (Wed Oct 2 2024 at 3:37 pm)
      - yep * - Plasma (Wed Oct 2 2024 at 8:13 pm)

Reply to this Message

Name
Subject

Message



No HTML is allowed, except for <code> <b> <i> <u> in the message only. All URLs and email addresses will automatically be converted to hyperlinks.

Forum

View Message

Reply to this Message