GetProfileStringW function (winbase.h)

Retrieves the string associated with a key in the specified section of the Win.ini file.

Note  This function is provided only for compatibility with 16-bit Windows-based applications, therefore this function should not be called from server code. Applications should store initialization information in the registry.
 

Syntax

DWORD GetProfileStringW(
  [in]  LPCWSTR lpAppName,
  [in]  LPCWSTR lpKeyName,
  [in]  LPCWSTR lpDefault,
  [out] LPWSTR  lpReturnedString,
  [in]  DWORD   nSize
);

Parameters

[in] lpAppName

The name of the section containing the key. If this parameter is NULL, the function copies all section names in the file to the supplied buffer.

[in] lpKeyName

The name of the key whose associated string is to be retrieved. If this parameter is NULL, the function copies all keys in the given section to the supplied buffer. Each string is followed by a null character, and the final string is followed by a second null character.

[in] lpDefault

A default string. If the lpKeyName key cannot be found in the initialization file, GetProfileString copies the default string to the lpReturnedString buffer. If this parameter is NULL, the default is an empty string, "".

Avoid specifying a default string with trailing blank characters. The function inserts a null character in the lpReturnedString buffer to strip any trailing blanks.

[out] lpReturnedString

A pointer to a buffer that receives the character string.

[in] nSize

The size of the buffer pointed to by the lpReturnedString parameter, in characters.

Return value

The return value is the number of characters copied to the buffer, not including the null-terminating character.

If neither lpAppName nor lpKeyName is NULL and the supplied destination buffer is too small to hold the requested string, the string is truncated and followed by a null character, and the return value is equal to nSize minus one.

If either lpAppName or lpKeyName is NULL and the supplied destination buffer is too small to hold all the strings, the last string is truncated and followed by two null characters. In this case, the return value is equal to nSize minus two.

Remarks

If the string associated with the lpKeyName parameter is enclosed in single or double quotation marks, the marks are discarded when the GetProfileString function returns the string.

The GetProfileString function is not case-sensitive; the strings can contain a combination of uppercase and lowercase letters.

A section in the Win.ini file must have the following form:

[section]
key=string
      .
      .
      .

An application can use the GetPrivateProfileString function to retrieve a string from a specified initialization file.

The lpDefault parameter must point to a valid string, even if the string is empty (that is, even if its first character is a null character).

Windows Server 2003 and Windows XP/2000:  Calls to profile functions may be mapped to the registry instead of to the initialization files. This mapping occurs when the initialization file and section are specified in the registry under the following keys:

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\IniFileMapping

When the operation has been mapped, the GetProfileString function retrieves information from the registry, not from the initialization file; the change in the storage location has no effect on the function's behavior.

The profile functions use the following steps to locate initialization information:

  1. Look in the registry for the name of the initialization file under the IniFileMapping key.
  2. Look for the section name specified by lpAppName. This will be a named value under the key that has the name of the initialization file, or a subkey with this name, or the name will not exist as either a value or subkey.
  3. If the section name specified by lpAppName is a named value, then that value specifies where in the registry you will find the keys for the section.
  4. If the section name specified by lpAppName is a subkey, then named values under that subkey specify where in the registry you will find the keys for the section. If the key you are looking for does not exist as a named value, then there will be an unnamed value (shown as <No Name>) that specifies the default location in the registry where you will find the key.
  5. If the section name specified by lpAppName does not exist as a named value or as a subkey, then there will be an unnamed value (shown as <No Name>) that specifies the default location in the registry where you will find the keys for the section.
  6. If there is no subkey or entry for the section name, then look for the actual initialization file on the disk and read its contents.
When looking at values in the registry that specify other registry locations, there are several prefixes that change the behavior of the .ini file mapping:
  • ! - this character forces all writes to go both to the registry and to the .ini file on disk.
  • # - this character causes the registry value to be set to the value in the Windows 3.1 .ini file when a new user logs in for the first time after setup.
  • @ - this character prevents any reads from going to the .ini file on disk if the requested data is not found in the registry.
  • USR: - this prefix stands for HKEY_CURRENT_USER, and the text after the prefix is relative to that key.
  • SYS: - this prefix stands for HKEY_LOCAL_MACHINE\SOFTWARE, and the text after the prefix is relative to that key.

Note

The winbase.h header defines GetProfileString as an alias which automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header winbase.h (include Windows.h)
Library Kernel32.lib
DLL Kernel32.dll

See also

GetPrivateProfileString

WriteProfileString