When to Use WIN.INI or a Private INI File

 Last reviewed: July 22, 1997
Article ID: Q74608
3.00 3.10 WINDOWS kbprg

The information in this article applies to:

  • Microsoft Windows Software Development Kit (SDK) for Windows versions 3.1 and 3.0

SUMMARY

An application should use a private profile (INI) file to store initialization information where possible rather than the main INI file in Windows, WIN.INI. Profile files are not designed for use as a database or a mass-storage device.

MORE INFORMATION

Applications use the profile functions in the Windows application programming interface (API) to save and retrieve initialization settings. The following profile functions are used with WIN.INI: 

   GetProfileInt
   GetProfileString
   WriteProfileString
Until Windows version 3.0, applications stored their initialization data in only one global place (WIN.INI). Windows version 3.0 added a complimentary set of functions to the Windows API to enable an application to store its initialization data in a private INI file. These functions are as follows: 

   GetPrivateProfileInt
   GetPrivateProfileString
   WritePrivateProfileString
The following factors provided the motivation for the addition of private INI files:
  • INI files are limited to 64K in size.
  • Windows ignores the portion of INI files past 64K. Therefore, if enough applications use WIN.INI rather than separate, private INI files, some of the user's INI data may be ignored.
  • No consistent way exists for users to remove old, unneeded information from the WIN.INI file. Typically, when an application is removed from the system, the files are deleted from the application's directory. However, the corresponding information may not be deleted from WIN.INI. Alternately, if initialization data is stored in a private INI file in the application's directory or in a file with the application's name, the user is much more likely to delete the obsolete information.
  • Windows uses a linear search to find information in INI files. Therefore, smaller INI files provide faster performance.

By default, INI files are created in the Windows directory. However, an application should always use a fully qualified path to a different directory because the Windows system directory is a shared resource in a Windows network setup.

Do not use the private profile functions with the WIN.INI file. Windows caches a copy of WIN.INI and one private INI file. This caching scheme may be confused if WIN.INI is altered using the private profile functions.

Applications should use INI files conservatively. Use as few sections and as few lines as possible. For example, do not save the coordinates of a window individually, as follows: 

   [window save pos]
   ul = 10
   ur = 10
   ll = 100
   lr = 100
Instead, use one line, as follows: 

   [save_pos]
   window=10 10 100 100
This is a more efficient use of space and is much faster.

Additional reference words: 3.00 3.10
KBCategory: kbprg
KBSubcategory: UsrIni
Keywords : kb16bitonly

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Last reviewed: July 22, 1997
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