Q107695: PRB: Updating Multiple Device= Lines in SYSTEM.INI

Article: Q107695
Product(s): Microsoft Windows Software Development Kit
Version(s): WINDOWS:3.1
Operating System(s): 
Keyword(s): kb16bitonly kbSDKPlatform kbSysSettings
Last Modified: 09-JUN-1999

3.00 3.10
WINDOWS
kbprg

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The information in this article applies to:

- Microsoft Windows Software Development Kit (SDK) 3.1 
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SYMPTOMS
========

When there is more than one entry with the same name under a section in an .INI
file, WritePrivateProfileString() and WriteProfileString() can update only the
first specified entry in the section.

STATUS
======

This behavior is by design.

MORE INFORMATION
================

For example, in the [386Enh] section of the SYSTEM.INI file, there are multiple
"device=" lines. If you want to add a new device= line or update one of the
device= lines other than the first device= entry, you cannot use
WritePrivateProfileString(). For example, the following call

     WritePrivateProfileString("386Enh", "device", "drvname.drv",
     "SYSTEM.INI");

will only replace the first device= statement with DRVNAME.DRV, instead of adding
a new device= line. The reason is that the Windows .INI file application
programming interfaces (APIs) in the Windows 3.1 SDK work only on unique entries
in a given section of the .INI file.

There are couple of options available to work around this situation:

- Open, parse, modify, and save the .INI file in your application. Note, that
  although Windows 3.1 supports direct file I/O to the INI files, Windows 3.0
  does not. Moreover, Windows caches INI files, and therefore if you modify a
  .INI file, the disk file is updated, however, the cache is not. To update the
  cache, call WriteProfileString(NULL, NULL, NULL), which forces a flush of the
  cache.

  -or-

- Win32 applications can use the APIs that support the multiple "entry=" lines
  in a single section of a .INI file. For example, you could use the
  WriteProfileSection() and WritePrivateProfileSection() functions in the Win32
  API.

  -or-

- Use the VxD services that WIN386.EXE uses when it loads all the devices
  listed in the device= lines of the [386Enh] section in SYSTEM.INI file. The
  services that the VxDs provide are documented in the Windows Device Driver
  Kit (DDK).

Additional query words: 3.10 3.00

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Keywords          : kb16bitonly kbSDKPlatform kbSysSettings 
Technology        : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK310
Version           : WINDOWS:3.1
Issue type        : kbprb

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