We help IT Professionals succeed at work.

We've partnered with Certified Experts, Carl Webster and Richard Faulkner, to bring you two Citrix podcasts. Learn about 2020 trends and get answers to your biggest Citrix questions!Listen Now


Mouse Driver on CA-Clipper 5.3

serginho asked
Medium Priority
Last Modified: 2008-03-03
How can I remove the mouse driver from the memory in CA-Clipper 5.3 applications ? I explain. In this program :


   If I compile it with Clipper 5.3, the browser shows me the mouse pointer, and I don't put anything command to show it, I don't want to show it. But, I know that MHide(), MPresent() and MSetCursor() functioins only Hide the mouse pointer. But I'd like to remove the mouse driver from memory. I need to do this because if I try to run a Clipper 5.3 application in a anwser machine of a company that I work (it has 4 modems - COM1,COM2,COM3 and COM4) the applications simply stops the proccess. I believe that application Stops because the Clipper application look for a mouse in COM1, and the machine has a MODEM in COM1. If I compile this program in CLipper 5.2, everything runs perfectly in this anwser machine (with 4 modems).
   I try everything yet. We contact the General Manager of CA in Latin America because nobody in CA knows how to solve this question...If anyone here has the anwser, please e-mail me, I'm desesperated.
Watch Question


Why don't you remove the mouse driver from autoexec.bat or config.sys?  Alternatively I have a freeware program that will allow you to remove any TSR.  You can remove the mouse driver just before calling the browse and then reinstall it if you wish.


But I don't have a mouse driver in AUTOEXEC.BAT !!! The machine's a 486-DX2 66 without keyboard, monitor or mouse and running under MS-DOS 5.00. The machine only anwser calls with 4 taks in DOS, each taks anwser one phone line. There're modems on COM1,COM2,COM3 and COM4.


Hi ! I need of this anwser. I contact the CA Support of Brazil and they also don't have an anwser...Please help me...

I have had many problems with Clipper 5.3.  I've given up on it and are use 5.2 mostly now.  Are there features in 5.3 that you need?


  Well, in fact I don't need to 5.3 features, but the company where I work buy the CA-Clipper 5.3. I can't use the CA-Clipper 5.2 because I don't have it here in the company. I think that CA doesn't accept that I change my 5.3 package by a 5.2 Package, doesn't it ? When I say that with 5.2 version always is ok, I did this with a illegal version of Clipper, but now I deleted it, and I've here only the 5.3 version (Legal version).

Why don't you fax or email CA, explain the problem & ask if it's OK to use 5.2?  I'm sure the 5.3 licence would cover you.  Besides, the compiled code doesn't need to be licenced, only the actual compiler itself.


I did this yet. I contact the CA's General Manager of South America because I had the information that here in Brazil there isn't free Clipper support for registred users, then I could pay R$ 150,00 (more or less US$ 135.00). Then I thought : I bought a product of a company and I don't have free support ? Then Why to buy this product ? Then My boss contact the CA's General Manager of South America to know this, and he say that this is the CA polic of support in Brazil. Well, Then There isn't anything to do. But I'll verify if I can use the 5.2 (illegal copy) having bought the 5.3 version. Thank you for your sugestion.

I used to think Nantucket was bad.  Then CA bought Clipper.  You're right, there is no support, just requests for money.

I'm here in the US.  I'll research the problem for you.  I think akb is correct in that you can use 5.2 if you are licensed for 5.3.  I _KNOW_ you can if you have upgraded, that is if you (your company) used to have 5.2 and upgraded to 5.3, you can still use 5.2.  I had this very conversation with CA just last week and informed them I was using 5.2 for most of my work.

I get the feeling though, that you (your company) never had a legal copy of 5.2.  That MAY be different.  Version 5.2 is NOT for sale anymore.  If CA says it is OK to use 5.2, is there a way I can get a copy of it to you?  I afraid I'm completely ignorant of things international.

Hang in there, we'll get a satisfactory answer.  I just LOVE yanking CA's chain!


I did a check of the documentation for version 5.3.  There are two functions you can use to determine where the problems lie.

MPRESENT()  -> lIsPresent

Mpresent() returns true .T. is a mouse is present; otherwise returns false .F.

For a mouse to be available, it must be physically installed in addition to loading the appropriate device driver.

The other function is MSTATE()

In the notes section it says to try this:

aState := MSTATE()
IF aState[LLM_STATE_DRIVER] <= 500
   // consider the mouse to be absent
   // consider the mouse to be present
END if

Most of the mouse function make a reference to Llibg.lib.  Are you including this library in the link?  Did you try eliminating it?
I had more trouble with that Lightlib crap than you could believe!  And, their support is actually worse than CA's

Check this out and get back to me.


If worse come to worse, I have a legal copy of 5.2.  You can email me the source & I'll compile it for you!


akb, of course that I won't send the source of any system for nobody ! Are you crazy ? System's sources may not sent (at least without a goooood payment before)...


Barthollis..I don't have any mouse and also any mouse driver in the machines. I'll tell (again) about the machines : They are 486-DX2 66 Mhz 8Mb RAM without mouse, without monitor and without keyboard. They are running MS-DOS 5.0. They have four modems in COM1,COM2,COM3,COM4. When I put A Clipper 5.3 application in this machine, the machine simply stops the proccess. But, with a Clipper 5.2 Application, Everything run perfectly. Then, When I doing a test in a Win95 machine with 5.3, I saw that there's a mouse pointer, then I think that Clipper 5.3 call a mouse in COM1, and I think this 's the response for the stopped of machine with Clipper 5.3 applications. Do you understand ? I don't want to know if there's a mouse present or not (I know that there isn't). I'd like to run my Clipper 5.3 application in this machines. Well, You may think that my machine is bad, ok ? Then, Here's a BBS, And there's 20 machines like this that anwser 80 lines (4 modems X 20 machines = 80 lines), and Clipper 5.3 application don't run in anyone.


I'm not crazy!  I didn't realise the code was that sensitive.  I was only trying to help!!!

Settle down.  Nobody's inferring you don't know what you're doing.  We're just trying to help.  I believe you when you say there is no mouse on the machine.  We all do!  You can see the machine!  You'd certainly see a mouse if it were there.

The functions I mentioned indicated they could test for a mouse DRIVER.  I thought that Clipper might install one its self as part of the Llibg.lib

Win 95 has a built in mouse driver and that is why you would see the pointer when you ran the app on that machine.  The machine that has the 4 com ports _should_ run the app ok.  I think you have run into one of those areas where the compiler manufacturer ASSUMED that one would be there.

I'm still doing some research on this end.  I'll be back later.


I contacted Computer Associates here in Islandia, New York which is the world headquarters.  They informed me that a license is NOT version specific.  You or your company may use a previous version of Clipper as long as you have a license for a current version.

Now, the question is, how to get a copy of 5.2 to your company.  Is the version you use in a language other than english?  Can you get along without the documentation?

It's 4:20 pm here right now.  CA's tech support will be giving me a call to discuss your situation.  However, I think it will probably be tomorrow before they do.

Let me make sure I have the EXACT situation.

Have you tried the software on the machine while you had a keyboard connected to it? (could it be looking for the keyboard instead of the mouse?)   I presume you have the com ports on different IRQs.  Would you let me know the addresses and IRQs you are using?

How was the software that is currently running on the other machines created?  Is it Clipper?  What version?

What libraries are you linking in when you compile the 5.3 version?

Obviously, there is no usable output to the display of you normally run the machine without a monitor.  Is there a display card in the machine?   VGA?


I have the answer for you although you are not going to like it.  
Microsoft changed some of the routines in their libraries which means the CA had to make changes to their routines.  Especially in the terminal and floating point drivers.  It affects the networking and memory management areas.

If you are using any third party libraries, they *must* be upgraded to work with 5.3 as 5.3 uses a Microsoft floating point library that is different than 5.2.  Without these changes, you will most certainly experience a hang.

If you have written any routines in C, again, you will have to recompile them using the current version of the C compiler.  The changes to the floating point library require this.

You almost certainly must be using something as Clipper is pretty weak in the handling of com ports by its self.

If you are using the Blinker linker, it *must* be version 3.30 or 4.1 or higher.  Any other version *will* cause troubles.

The problem is in the floating point libraries, not the mouse.  You can  _not_ disable the mouse driver in 5.3 although IT is not what is causing the problem.

The fact that the program will operate under Windows 95 is proof that the problem is within the floating point and memory management section.  Windows pulls in the correct memory .DLLs to compensate.

According to CA, you should be able to run your program under Windows, even 3.1 however, I don't think that is an acceptable solution as Windows is certain to have trouble with no keyboard, mouse or monitor.  You could, of course, verify this by temporarily installing windows and running your application.

Your version of Clipper should be patched to level B.  This requires you to install the level A patch first, then level B.

If you can recompile any C routines and/or upgrade any third party libraries, you should be able to use 5.3 successfully.

If you decide to use 5.2, it should be patched to level E

Sorry I couldn't come up with a simpler solution.  Let me know what you decide.


Not the solution you were looking for? Getting a personalized solution is easy.

Ask the Experts
Access more of Experts Exchange with a free account
Thanks for using Experts Exchange.

Create a free account to continue.

Limited access with a free account allows you to:

  • View three pieces of content (articles, solutions, posts, and videos)
  • Ask the experts questions (counted toward content limit)
  • Customize your dashboard and profile

*This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.


Please enter a first name

Please enter a last name

8+ characters (letters, numbers, and a symbol)

By clicking, you agree to the Terms of Use and Privacy Policy.