Virtual User Q&As

Technote PT 600October 1990

Revised by: Developer Support Center September 1993
Written by: Developer Support Center October 1990

This Technical Note contains a collection of archived Q&As relating to a specific topic--questions sent the Developer Support Center (DSC) along with answers from the DSC engineers. Current Q&A's can be found on the Macintosh Technical Q&A's web site.

Path to AppleLink's Virtual User forum

Date Written: 1/9/91

Last reviewed: 1/24/91

What is the path to the Virtual User (VU) forum on AppleLink, mentioned in the Virtual User 1.0ß5 Release Notes?


The path for this discussion is "Developer Support:Developer Talk:Macintosh Developer Tools Discussions:Virtual User Discussion."

Macintosh Virtual User C++ headers

Date Written: 1/9/91

Last reviewed: 1/24/91

Do the MacApp Units for Virtual User (VU) work with C++ and MacApp?


The MacApp Units for VU should work fine with C++. In the VU discussion folder on AppleLink you'll find a file called C++ Header Assist (or something like that). These are the C++ headers for VU, from Apple Europe. A VU engineer here says to his knowledge, the headers work fine, though he hasn't tested them thoroughly. "Official" C++ headers should be available in the next month or so.

Virtual User workaround for setting an individual list element

Date Written: 1/23/91

Last reviewed: 2/14/91

How do you set an individual element of a list using the Macintosh Virtual User tool? When using the following code, the second line results in a syntax error.

    x:={1,2,3,4,5}; #define a list
    x[2]:=5;        #change the 2nd element of list x
    printlt x[2];   # print to log file the value of the 2nd element of list x

You're right! I'm amazed, but I just tried it myself and got a syntax error. To work around this, I would suggest that you try to concatenate the left and right portions of the list to the new middle value. For example, if you want to change the second element of the list, concatenate the first element with your new value, and concatenate that result with the remaining elements in the list.

To make up for this deficiency, we have provided some system tasks in the language which help manipulate lists, such as

    insert (element, index, list)
    replace (element, index, list) and
    remove (index, list)

These system tasks are described in Appendix F of the Virtual User Language Reference. (With future releases, you probably will be able to assign a value directly to a list element.)

Macintosh Virtual User testing system is compatible with A/UX

Date Written: 11/21/89

Last reviewed: 1/23/91

Does Virtual User 1.0ß5 run on an A/UX system? If so, are there any special versions needed to be running this?


You should have no problem running VU on A/UX. If you do run into any problems, you might want to try upgrading to A/UX 2.0.1 (as opposed to 2.0), because VU was revised for compatibility with 2.0.1 and it may not be totally backwards compatible. But as far as I know, it should work fine with either version with no special enhancements needed.

Virtual User and Macintosh Plus keyboard

Date Written: 8/21/91

Last reviewed: 9/17/91

Can I use a Macintosh Plus with an international keyboard as a Virtual User (VU) host?


Unfortunately, VU currently does not fully support the Macintosh Plus international keyboard. The VU General Reference manual (page 60) states, "key events for keys on this keyboard which have key codes that differ from those of the U.S. version of the keyboard will not be generated properly. The ASCII value portion of the key event will be correct but the key code will not be correct. This should only affect applications which use the key code portion of key events."

AppleLink's Virtual User forum is a good resource

Date Written: 8/21/91

Last reviewed: 9/17/91

When you have Virtual User (VU) questions, you can usually obtain fast answers via AppleLink's Virtual User forum from other developers as well as the VU authors monitoring the forum. The path to access this discussion is: Developer Support:Developer Talk:Macintosh Development Tool Discussions:Virtual User Discussion.

Previous Technote | Contents