.COM programming in DOS

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Khumba

.COM programming in DOS

Post by Khumba »

Hello. I was wondering if I make my own .COM
program and add SHELL=FILE.COM to my config.sys,
do I still have access to interrupt 21h, or is
that interrupt part of COMMAND.COM? Thanks.


-- Khumba --
-- "Lose your questions and you will find your answers" -D'ni proverb
Guest

RE:.COM programming in DOS

Post by Guest »

21H is not part of command.com
Please do let us know if it works!

>On 2002-01-30 18:11:57, Khumba wrote:
>Hello. I was wondering if I make my own .COM
>program and add SHELL=FILE.COM to my config.sys,
>do I still have access to interrupt 21h, or is
>that interrupt part of COMMAND.COM? Thanks.
>
>
>-- Khumba --
> -- "Lose your questions and you will find your answers" -D'ni proverb
Guest

RE:.COM programming in DOS

Post by Guest »

Yes! Thank you, I will try making an example then!

>21H is not part of command.com
>Please do let us know if it works!
>
>>On 2002-01-30 18:11:57, Khumba wrote:
>>Hello. I was wondering if I make my own .COM
>>program and add SHELL=FILE.COM to my config.sys,
>>do I still have access to interrupt 21h, or is
>>that interrupt part of COMMAND.COM? Thanks.
>>
>>
>>-- Khumba --
>> -- "Lose your questions and you will find your answers" -D'ni proverb
Guest

RE:.COM

Post by Guest »

It should work, int21 is owned by io.sys, command.com is the prompt only

>On 2002-01-31 11:13:21, Anonymous wrote:
>Yes! Thank you, I will try making an example then!
>
>>21H is not part of command.com
>>Please do let us know if it works!
>>
>>>On 2002-01-30 18:11:57, Khumba wrote:
>>>Hello. I was wondering if I make my own .COM
>>>program and add SHELL=FILE.COM to my config.sys,
>>>do I still have access to interrupt 21h, or is
>>>that interrupt part of COMMAND.COM? Thanks.
>>>
>>>
>>>-- Khumba --
>>> -- "Lose your questions and you will find your answers" -D'ni proverb
Khumba

RE:.COM

Post by Khumba »

(Whoops, forgot to add my name on the third post)
Okay, good. Is io.sys is automatically loaded, or
do I have to load it myself?

>On 2002-01-31 12:29:52, Anonymous wrote:
>It should work, int21 is owned by io.sys, command.com is the prompt only
>
>>On 2002-01-31 11:13:21, Anonymous wrote:
>>Yes! Thank you, I will try making an example then!
>>
>>>21H is not part of command.com
>>>Please do let us know if it works!
>>>
>>>>On 2002-01-30 18:11:57, Khumba wrote:
>>>>Hello. I was wondering if I make my own .COM
>>>>program and add SHELL=FILE.COM to my config.sys,
>>>>do I still have access to interrupt 21h, or is
>>>>that interrupt part of COMMAND.COM? Thanks.
>>>>
>>>>
>>>>-- Khumba --
>>>> -- "Lose your questions and you will find your answers" -D'ni proverb
The Legend

RE:.COM

Post by The Legend »

io.sys is automatically loaded by the ms dos boot
loader. I think it was first io.sys, which loads
msdos.sys (or the boot loeader did that, too) and
msdos.sys should parse the config.sys!

>On 2002-02-01 11:10:05, Khumba wrote:
>(Whoops, forgot to add my name on the third post)
>Okay, good. Is io.sys is automatically loaded, or
>do I have to load it myself?
>
>>On 2002-01-31 12:29:52, Anonymous wrote:
>>It should work, int21 is owned by io.sys, command.com is the prompt only
>>
>>>On 2002-01-31 11:13:21, Anonymous wrote:
>>>Yes! Thank you, I will try making an example then!
>>>
>>>>21H is not part of command.com
>>>>Please do let us know if it works!
>>>>
>>>>>On 2002-01-30 18:11:57, Khumba wrote:
>>>>>Hello. I was wondering if I make my own .COM
>>>>>program and add SHELL=FILE.COM to my config.sys,
>>>>>do I still have access to interrupt 21h, or is
>>>>>that interrupt part of COMMAND.COM? Thanks.
>>>>>
>>>>>
>>>>>-- Khumba --
>>>>> -- "Lose your questions and you will find your answers" -D'ni proverb
Guest

RE:.COM programming in DOS

Post by Guest »

Sorry this took so long, (I kinda forgot about it),
but I got it working! Here's how to set it up:

1. Go to a DOS prompt
2. Type FORMAT A: (or whatever drive you want to use)
3. Type SYS A:
4. Download this file and unzip it to the disk:
http://www.geocities.com/cksdev/comos/comos.zip
NOTE: If you have MSIE v6 for Win98, like me you
may need to take off the "comos.zip" part to go
to the directory, then download the file seperately.
5. Reboot!

I hope this works, it did for me. I haven't tested
it out with FREEDOS or others, just MS-DOS. Good luck!

>On 2002-01-30 18:11:57, Khumba wrote:
>Hello. I was wondering if I make my own .COM
>program and add SHELL=FILE.COM to my config.sys,
>do I still have access to interrupt 21h, or is
>that interrupt part of COMMAND.COM? Thanks.
>
>
>-- Khumba --
> -- "Lose your questions and you will find your answers" -D'ni proverb
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