DOS ain't dead - polling

polling (Announce)

posted by Japheth , Germany (South), 01.06.2011, 17:50

> > From my experience I'd say that this variant of "idle call" isn't
> supported
> > in NTVDM ( I am not 100% sure).
>
> You are wrong; it is indeed supported.

Yes, partially. I recall the issue now: it isn't supported by NTVDM if the DOS app is in protected-mode. It's somewhat funny that the call is supported in real-mode, but not in protected-mode, because, IIRC, this API was introduced with DPMI.

> > Although it sounds a bit strange, probably
> > the best option in NTVDM is to call the "keyboard status interrupt" (int
> > 16h, ah=01) if you want to "give up" your time slice.
>
> Are you sure? That sounds indeed strange. Isn't 16.01 supposed to return
> immediately? In any case mTCP's DHCP (other programs probably too) does
> appear to call 16.01 in each loop iteration so if that gave up enough time
> it wouldn't fully load a core.

Yes, it is supposed to return immediately. I guess the NTVDM hooks this interrupt and will go idle if it is called "too often".

---
MS-DOS forever!

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Complete thread:

mTCP Open Source release - mbbrutman, 27.05.2011, 23:47 (Announce)
- mTCP GPL - ecm, 27.05.2011, 23:58
  - GPLv3 - mbbrutman, 28.05.2011, 00:20
    - GPL: either version 3 of the license, or any later version - ecm, 28.05.2011, 00:55
      - GPL: either version 3 of the license, or any later version - mbbrutman, 28.05.2011, 01:09
        GPL: either version 3 of the license, or any later version - ecm, 28.05.2011, 01:18
        GPL: either version 3 of the license, or any later version - mbbrutman, 28.05.2011, 01:25
        download, compile, ... - ecm, 28.05.2011, 01:30
        GPL: either version 3 of the license, or any later version - marcov, 30.05.2011, 09:37
        GPL: either version 3 of the license, or any later version - mbbrutman, 30.05.2011, 15:32
        What does the GPL allow? - ecm, 30.05.2011, 16:08
        What does the GPL allow? - mbbrutman, 30.05.2011, 16:30
        GPL something - ecm, 30.05.2011, 17:08
        GPL something - mbbrutman, 30.05.2011, 18:05
        theoretical licensing problems and such - ecm, 30.05.2011, 18:28
        licensing again... executables - ecm, 30.05.2011, 22:34
        licensing again... executables - mbbrutman, 31.05.2011, 03:33
        licensing again... executables - ecm, 31.05.2011, 13:59
        licensing again... executables - mbbrutman, 01.06.2011, 01:16
        licensing again... executables - ecm, 01.06.2011, 01:53
        licensing again... executables - mbbrutman, 01.06.2011, 02:17
        licensing again... executables - ecm, 01.06.2011, 15:49
        What does the GPL allow? - Rugxulo, 30.05.2011, 18:14
        mTCP in DOSEMU; Linux kernel developers' GPLv2-only reasons - ecm, 30.05.2011, 22:38
        What does the GPL allow? - marcov, 30.05.2011, 22:49
        What does the GPL allow? - mbbrutman, 31.05.2011, 03:41
        What does the GPL allow? - mbbrutman, 31.05.2011, 04:18
        What does the GPL allow? - Japheth, 30.05.2011, 18:47
        Gift trolls and other curiosities - ecm, 30.05.2011, 19:20
        Gift trolls and other curiosities - mbbrutman, 30.05.2011, 19:54
        editing - ecm, 30.05.2011, 20:03
        What does the GPL allow? - marcov, 30.05.2011, 22:38
        What does the GPL allow? - marcov, 30.05.2011, 22:37
        GPL: either version 3 of the license, or any later version - marcov, 30.05.2011, 22:35
        GPL: either version 3 of the license, or any later version - mbbrutman, 30.05.2011, 22:56
        GPL: either version 3 of the license, or any later version - marcov, 02.06.2011, 16:10
        GPL: either version 3 of the license, or any later version - mbbrutman, 03.06.2011, 04:12
        GPL: either version 3 of the license, or any later version - marcov, 03.06.2011, 13:36
        GPL: either version 3 of the license, or any later version - Rugxulo, 03.06.2011, 16:45
- mTCP and SwsVPkt - Japheth, 31.05.2011, 09:03
  - mTCP and SwsVPkt - mbbrutman, 01.06.2011, 03:11
    - mTCP and SwsVPkt - Japheth, 01.06.2011, 13:14
      - mTCP and SwsVPkt - mbbrutman, 01.06.2011, 15:04
    - polling - ecm, 01.06.2011, 16:07
      - polling - Japheth, 01.06.2011, 17:12
        polling - ecm, 01.06.2011, 17:27
        polling - Japheth, 01.06.2011, 17:50
        polling - ecm, 01.06.2011, 17:55
        polling - Japheth, 01.06.2011, 18:39
        polling - ecm, 01.06.2011, 18:49
        polling - Rugxulo, 02.06.2011, 00:37
        polling - ecm, 02.06.2011, 00:52
        polling - Japheth, 02.06.2011, 05:42
        polling - mbbrutman, 04.06.2011, 04:13
        polling - ecm, 04.06.2011, 06:50
        polling - Arjay, 04.06.2011, 10:46
        polling - mbbrutman, 16.07.2011, 22:09
        polling - Ninho, 17.07.2011, 12:59
        polling - mbbrutman, 17.07.2011, 23:05
        polling - Ninho, 18.07.2011, 11:22
        polling - mbbrutman, 18.07.2011, 16:05
        polling - Ninho, 18.07.2011, 17:28
        IGNORE! no text, posting error - Ninho, 18.07.2011, 17:30
        polling - mbbrutman, 18.07.2011, 17:41
        polling - ecm, 21.08.2011, 16:28