Appendix B - Windows 98 System File Details

This appendix provides details about the system files supplied with Microsoft Windows 98.

See Also

• For information on how to create a Windows 98 Startup Disk, see Chapter 2, "Setting Up Windows 98." 

• For information on how to use a Windows 98 Startup Disk, see Chapter 5, "Setup Technical Discussion." 

Distribution Disk Storage Overview

Windows 98 is stored on the distribution disks as cabinet (CAB) files. When the Windows 98 disks are created, files are compressed into folders. The Windows 98 files are read in and written out as a continuous byte-stream. The entire stream is compressed and divided into folders as appropriate. Folders can fill one or more cabinets. The following defines the terms used to describe the distribution files.

Cabinet A file that contains one or more files, usually compressed.

Folder A decompression boundary. Large folders enable higher compression, because the compressor can refer back to more data in finding patterns. However, to retrieve a file at the end of a folder, the entire folder must be decompressed.

The Windows 98 distribution disks use distribution media format (DMF), which is a special read-only format for 3.5-inch floppy disks that permits storage of 1.7 MB of data.

Cabinet File Structure

The file structure introduced in Windows 95 has changed slightly in Windows 98. In Windows 95, most of the files were contained in a Win95#.cab structure. The rest of the files were included in the Base#.cab, Catalog.cab, Driver#.cab, Mini.cab, and Precopy#.cab cabinets.

Windows 98 instead groups CAB files by function. The following table summarizes the cabinet files and their contents.

The # in the file names uses the following naming convention:

• Base4.cab through Base5.cab 

• Driver11.cab through Driver21.cab 

• Net6.cab through Net10.cab 

• Precopy1.cab through Precopy2.cab 

• Win98_22.cab through Win98_69.cab 

Organizing the CAB files in this manner allows for easier extraction and a smoother setup. For example, if the computer does not have a network card, the Net#.cab files are not moved to the user's computer during setup.

Viewing and Extracting Cabinet Files Using Explorer

In Windows 98, you can view and extract CAB files using Windows Explorer. In Windows 95, you had to use the command-line Extract program to extract CAB files.

To view the contents of a CAB file with Windows Explorer

1. Click the Start button, point to Programs, and then click Windows Explorer. 

2. In the left pane, click the letter that represents the drive where the CAB files are located. 

3. Navigate to the folder containing the CAB file you want to view. 

4. On the right pane, double-click the CAB file you want to view. 

   The contents of the CAB file appear in a separate window. 

To extract CAB files with Windows Explorer

1. Follow the instructions for viewing the contents of a CAB file. 

2. In the window displaying the contents of the CAB file, double-click the file you want to extract. 

   The Browse for Folder dialog box appears. 

3. Click a folder in which to save the file you are extracting, and then click OK. 

You can also extract files by using System File Checker, as described in Chapter 27, "General Troubleshooting." With System File Checker, you do not need to know which CAB file contains the file you need.

Extracting CAB Files Using the Extract Program

The Extract program supports command-line extraction of files from the CAB storage format on disk. Extract does not support any other compression system (that is, it is not backward-compatible with any previous Microsoft disk utilities).

The Extract program (Extract.exe) can be found in the \Windows\Command directory or on the Windows 98 installation media.

Important In general, use the Extract program only if your product support representative indicates that using the Extract program is necessary to retrieve a compressed file from the Windows 98 cabinet files.

Under normal circumstances, you should use the Add/Remove Programs or Network icon in Control Panel to install and uninstall components, applications, and support software from the Windows 98 installation media.

If system files are missing or damaged, run Windows 98 Setup from the Windows 98 installation media, and choose the option to validate and restore files.

Syntax

extract [/y] [/A] [/D | /E] [/L location] cabinet_file [file_specification ...]

– Or –

extract [/y] compressed_file [destination_file]

– Or –

extract [/y] /C compressed_file destination_file 

Parameters

/A 

Process all files in a cabinet set, starting with the cabinet_file. Follow cabinet chain.

/C 

Copy source file to destination (to copy from DMF disks).

/D 

Display cabinet directory. Do not extract.

/E 

Use instead of *.* to extract all files.

/L location  

Use the directory specified by location, instead of the current directory, as the default location to place extracted files.

/Y 

Overwrite files in the destination without prompting. The default is to prompt the user if the destination file already exists, and to allow one of the following:

• Overwrite the file.

• Skip the file. 

• Overwrite this file and all subsequent files that may already exist. 

• Exit. 

compressed_file

This is a CAB file that contains a single file (for example, File1.ex_, which contains File1.exe). If destination_file is not specified, the file is extracted and given its original name in the current directory.

destination_file

This can be either a relative path (.:, .., C:File1, and so on) or a fully qualified path. It can specify either a file (or files, if wildcards are included) or a directory. If a directory is specified, the file name stored in the cabinet is used. Otherwise, destination_file is used as the complete file name for the extracted file.

cabinet_file

This is a CAB file that contains two or more files. If no file_specification parameter is specified, a list is displayed of the files in the cabinet. If one or more file_specification parameters are specified, then these are used to select the files to be extracted from the cabinet. Wildcards are allowed to specify multiple cabinets.

file_specification

This specifies files to be extracted from the cabinets. This can contain the ? and * wildcards. Multiple file_specification values can be supplied.

The following table provides some examples.

For more information about the Extract program, see Knowledge Base article 129605, "How to Extract Original Compressed Windows Files."

Setup Files Overview

The following table describes the key files used for Windows 98 Setup.

Also, the Wininstx.400 directory is created at the beginning of the Windows 98 Setup process. This directory contains a minimal set of files used during setup and requires about 10 to 12 MB of free disk space. This directory is removed upon the successful completion of Windows 98 installation.

Directory File Structure and File Locations

The following figure shows the typical default directory structure created for Windows 98. The bold entries are new entries in Windows 98.

Location of Key System Files

The following table lists the directories where various types of Windows 98 system files and supporting files are stored.

The following list shows where key Windows 98 files are stored when Windows 98 is installed on the local hard disk of a computer.

Location of System Files on Compressed Disks

If you install Windows 98 on a compressed drive, Windows 98 Setup places the following files on the boot drive.

When Windows 98 is installed on an uncompressed drive other than the startup drive, Setup adds the same files (with the exception of Drvspace.ini) to the boot drive, as listed earlier in this section. The only difference is that Win386.swp will be placed on the same drive as the Windows directory. For example, if you have drives C and D, and if you install Windows 98 on D:\Windows, Win386.swp will be on the root of D. Otherwise, it will be placed as described earlier for compressed drives.

The Windows 98 Startup Disk

The Windows 98 Startup Disk has changed significantly for Windows 98. The following functionality has been added:

• Multi-start menu for booting your computer with or without access to the CD-ROM. 

• Real-mode IDE CD-ROM support 

• Real-mode SCSI CD-ROM support 

• Edb.cab file 

• RAMdrive 

• New extract command (Ext.exe) 

For more information on how to make a Startup Disk, how to use it, and its new functionality, see Chapter 2, "Setting Up Windows 98" and Chapter 5, "Setup Technical Discussion."

The Edb.cab File

The Edb.cab file contains several utilities. It is a compressed file whose contents are expanded during the startup process. The following table lists the contents this file.

Contents of the Windows 98 Startup Disk

The following table lists the contents and describes the function of each file in the Startup Disk.

Note The files contained in the Startup Disk are copied to the \Windows\Command directory only if the user chooses to create a Windows 98 startup disk during Setup. This happens during the first phase of the Startup Disk creation process. If you create a startup disk from Control Panel (From the Startup Disk property page in Add/Remove Programs) and the startup disk files are not in the \Windows\Command directory, you will prompted for the Windows 98 compact disk. A startup disk will be created but its contents will not be copied locally when you use this method.