PRB: Repeated Blank Screens During Build Process in VC++

• The development environment, included with: Microsoft Visual C++, 32-bit Editions, versions 2.0, 2.1, 2.2, 4.0, 4.1, 4.2, and 5.0

SYMPTOMS

When you build from the development environment in Visual C++, the screen repeatedly flashes to a blank text mode screen with no text on it. A text cursor may show up if you move the mouse while the blank screen is showing. The screen returns to Visual C++ and then blanks out again. The blanking occurs at least twice but possibly more times during the entire build process.

CAUSE

The default settings for the Command Prompt on Windows NT or Windows95 is set to full screen.

RESOLUTION

Depending on whether you are on Windows NT or Windows95, the resolution process is different.

1. For Windows NT you must set the options for one of the following to "Windowed."

   - The environment settings of all Windows NT Command Prompts.

        -or-
   

   - The program Vcspawn.exe, which Visual C++ runs as a background

        process.
   

2. For Windows95, you must reset the options for one or all of the following.

   _Default.pif Conagent.exe

MORE INFORMATION

On Windows NT, Visual C++ repeatedly invokes a background process called Vcspawn.exe for each command-line tool executed by the development environment. Tools such as Cl.exe, Link.exe, and Bscmake.exe run in the Vcspawn.exe environment, which is a 32-bit console application.

Usually Vcspawn.exe is invoked as a hidden window and you never see it. However, if the setting for Vcspawn.exe is in "full screen" mode, the screen switches to text mode each time Vcspawn.exe is invoked. No text is actually sent to the vcspawn screen, so the screen appears blank.

On Windows95, Vcspawn.exe is affected by the presence of the _Default.pif and the settings of the Conagent.exe file. If a _Default.pif is in the path, its properties will be used for all invoked console applications. Often, a _Default.pif will be left over from a previous Windows 3.1 or 3.11 installation. Windows95 will not create one itself during installation. If _Default.pif is not present, Windows95 will use the properties of Conagent.exe.

On WINDOWS NT :

Use one of the following procedures to correct the problem.

Steps to Reset Default Configuration of ALL Command Prompts

1. Go to the Windows NT Control Panel.

2. Double click the Console icon.

3. Choose the General Settings or Options tab.

4. Select Window under the Display Options group.

5. Click OK.

   - or -

Steps to Reset Configuration for Just Vcspawn.exe by Using Regedt32

Use the following process to add a registry entry so only vcspawn's settings are not "full screen."

1. Run Regedt32, which is located in the \System32 subdirectory of the Windows NT root directory.

2. Open \HKEY_CURRENT_USER\Console branch of the registry tree.

3. Choose Add Key on the Edit menu to add a node called:

         C:_MSVC20_BIN_vcspawn.exe
   

   If Visual C++ is installed in a different directory or on a different drive, use the following form for the Key Name:

         <drive>:_DIR1_DIR2_DIR3..._vcspawn.exe
   

   Leave the Class field empty.

4. With "C:_MSVC20_BIN_vcspawn.exe" highlighted, click Add Value on the Edit menu. In the Value Name, type: FullScreen. In the Data Type, choose REG_DWORD. Click OK, and then add a value of 0 (zero).

5. Exit the registry editor, and restart Visual C++.

   - or -

Steps to Reset Configuration for Just Vcspawn.exe Without Using Regedt32

If you are not familiar with the system registry and do not want to reset the default configurations for the Command Prompt, use the following procedure to reset the settings for vcspawn. This procedure adds the same registry entry.

NOTE: if you have a fast machine, you may have trouble performing some of the following steps and you need a larger project. Therefore, if you have a fast machine, use one of the previous methods to work around the problem.

If you are compiling a large project, you can switch tasks and see the minimized Vcspawn.exe icon. Resetting the attributes of this icon will reset the attributes of vcspawn.

1. Open a large project, such as the sample project CTRLBARS, or SUPERPAD supplied with Visual C++.

2. Choose to "Rebuild All."

3. Press ALT+TAB to see the minimized vcspawn icon in the corner of the screen.

4. Quickly open the system menu, and follow the steps shown in the "Steps to Reset Default Configuration of ALL Command Prompts" section of this article.

ON WINDOWS 95 :

Use one of the following procedures to correct the problem.

Steps to Reset Configuration of _Default.pif

1. In the Explorer, choose the _DEFAULT file with the MS-DOS icon next to it in your Windows95 directory.

2. Single click the right mouse button. Choose "Properties".

3. Select the "Screen" tab.

4. Choose the "Window" option and click on "Apply" and then "OK".

   - or -

Steps to Reset Configuration of Conagent.exe

1. Make sure there is no _Default.pif file in your path, specifically check your Windows95 directory.

2. Follow the instructions for steps 2, 3, and 4 above given for resetting _Default.pif on the file Conagent.exe in your Windows95 directory.