• DOSEMU, PKZIP and DPMI

    From Dan Clough@1:123/115 to All on Saturday, June 29, 2019 20:08:00
    Hi all, I'm reposting the below message, with the original
    author's permission, because I think it may be helpful to many
    sysops...


    * Originally in: FSXnet BBS Support/Dev
    * Originally on: 06-29-19 20:40
    * Originally by: Netsurge

    PKZIP and dosemu don't play very well, especially if you are using a 64bit linux os.

    There is a way to disable DPMI (which causes the issue) via command line,
    by adding -) to the command line, but that really doesn't help if the zip
    and unzip routines are hardcoded into software, like interlord.

    Alas, after a shit load of research I have found a work around.

    First you will need pkzip 2.04g (google for pkz204g.exe or ask me to drop it
    in your inbound).

    Create a directory via dosemu to house pkzip and pkunzip (I created one in my doors dir called pkzip).

    Copy and run pkz204g.exe, it should uncompress all the PK stuff into doors/pkzip.

    Create a file in your pkzip dir called pkzip.cfg and add the following to
    that file:

    DPMI=Disabled

    Next you need to set the path for your pkzip folder and disable dpmi for pkunzip via your autoexec.bat. Edit autoexec.bat and add the following to
    your path statement:

    d:\doors\pkzip (where ever your created your pkzip folder)

    so my path statement looks like this now:

    path z:\bin;z:\gnu;z:\dosemu;d:\doors\pkzip

    you also need to add the following to your autoexec.bat file right after your last lredir statement:

    SET PKUNZIP=-)

    Now exit out of dosemu and head back into it so that your new autoexec.bat takes effect.

    As to why PKZIP uses a cfg file and PKUNZIP requires a variable set is beyond me, why not use either or for both. Then again, we are talking about the
    90's here/

    You should now be able to run pkzip.exe and pkunzip.exe from any directory without getting the dreaded DPMI error.

    If you have any questions, there is a huge discussion on SciNet in the
    gaming echo about beating dosemu into submission when it comes to running
    old dos door games in linux.

    |15frank |08// |15netsurge
    |07disksh0p|08!|07bbs |08% |07bbs.diskshop.ca |08% |07mystic goodness |11SciNet |03ftn hq |08% |07https://diskshop.ca/scinet

    === Mystic BBS v1.12 A43 2019/03/02 (Linux/64)
    # Origin: % disksh0p!bbs % bbs.diskshop.ca % SciNet ftn hq % (21:4/154)
    --- SBBSecho 3.07-Linux
    * Origin: Palantir * palantirbbs.ddns.net * Pensacola, FL * (1:123/115)
  • From Dan Clough@1:123/115 to mark lewis on Wednesday, July 03, 2019 10:50:00
    mark lewis wrote to Dan Clough <=-

    FreeDOS) under Slack64 and haven't had problems. But I think this
    issue only shows itself with certain doors/programs. Frank was
    having trouble with a particular door he was trying to get going.

    but it isn't the door causing the problem... it is pkzip and
    pkunzip that are... the door is likely not even running at that
    point... oh, wait... unless it is shelling out to (un)archive
    interbbs game packets... hummm...

    Yes, that is what I meant to say. The issue did involve Interbbs
    stuff and using pkzip/pkunzip from within DOSemu.


    ... A day without sunshine is like night.
    === MultiMail/Linux v0.52
    --- SBBSecho 3.07-Linux
    * Origin: Palantir * palantirbbs.ddns.net * Pensacola, FL * (1:123/115)
  • From mark lewis@1:3634/12.73 to Dan Clough on Wednesday, July 03, 2019 09:55:02
    On 2019 Jul 03 12:50:00, you wrote to me:

    but it isn't the door causing the problem... it is pkzip and pkunzip
    that are... the door is likely not even running at that point... oh,
    wait... unless it is shelling out to (un)archive interbbs game
    packets... hummm...

    Yes, that is what I meant to say. The issue did involve Interbbs
    stuff and using pkzip/pkunzip from within DOSemu.

    yeah, some of them do it in the script file that executes the door... others have a tool that shells out to extract the data packets and import them... it is possible that shelling out is causing problems...

    when i was running my RA system on OS2, my OLMS mail door started mucking up and ""crashing"" the node when it went to shell out to pack up the new messages... i write ""crashing"" but what it was on the screen was a supposed memory error and the node was in a tight loop... the only way out was to close the task and reset it... the problem happened for a while and then would go away for a while... then it would come back again...

    i suspect it was something to do with the DRM protections but don't have any proof... since the author released a generic registration key when they got out
    of BBSing and supporting OLMS, that's what i used because they were already gone by the time i decided to use the door... it is possible that it was simply
    a bug, too... maybe in OLMS or possibly in 4DOS... i dunno... it happened exactly the same in 4 different versions of 4DOS and i know that i've implemented DRM protections in some of my programs that did similar antics as what i was seeing...

    if i could have contacted the author, i would have... possibly even offered to take over the project but all contact information was scrubbed and he wasn't showing up in any searches so... oh well :shrug:

    )\/(ark

    And to this end they built themselves a stupendous super-computer which was
    so amazingly intelligent that even before its data banks had been connected
    up it had started from "I think therefore I am" and got as far as deducing
    the existence of rice pudding and income tax before anyone managed to turn
    it off.
    ... Never lick a gift horse in the mouth.
    ---
    * Origin: (1:3634/12.73)
  • From Dumas Walker@1:2320/105 to SEAN DENNIS on Saturday, July 06, 2019 15:05:00
    PKZIP and dosemu don't play very well, especially if you are using a 64bit linux os.

    That's odd. The past five years that I've used DOSemu with PC-DOS 2000 under Slackware 64 Linux with MBSE I haven't had a single issue...I wonder what version of DOSemu was used.

    Maybe one of the variables is that you are using PC-DOS 2000. I have had difficulties (sometimes) with the default freedos kernel on a 64-bit linux machine. There are workaround for the pkzip issue, but there are others
    that are pervasive.

    Someone else has reported having luck using an older MS-DOS kernel... 5.0,
    I think. I have that one so I thought I would try it sometime.

    Mike

    ---
    * SLMR 2.1a * Oooo, Better run, Mr. Wino!!!
    * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)
  • From Daryl Stout@1:19/33 to SEAN DENNIS on Saturday, July 06, 2019 08:35:00
    Sean,

    (No, I didn't pick the tagline. :D)

    ... Everyone is entitled to my opinion.

    But, I'm stealing it. <G>

    Daryl

    ===
    þ OLX 1.53 þ What color is a chameleon in a mirror??
    --- SBBSecho 3.07-Win32
    * Origin: The Thunderbolt BBS - tbolt.synchro.net (1:19/33)