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 GetEnvironmentVariable

Retrieves the contents of the specified variable from the environment block of the calling process.

Syntax

    DWORD WINAPI GetEnvironmentVariable(
      __in_opt   LPCTSTR lpName,
      __out_opt  LPTSTR lpBuffer,
      __in       DWORD nSize
    );

Parameters

• lpName
  The name of the environment variable.
• lpBuffer
  A pointer to a buffer that receives the contents of the specified environment variable as a null-terminated string. An environment variable has a maximum size limit of 32,767 characters, including the null-terminating character.
• nSize
  The size of the buffer pointed to by the lpBuffer parameter, in characters.

Return Value

If the function succeeds, the return value is the number of characters stored in the buffer pointed to by lpBuffer, not including the terminating null character.

If lpBuffer is not large enough to hold the data, the return value is the buffer size, in characters, required to hold the string and its terminating null character.

If the function fails, the return value is zero. If the specified environment variable was not found in the environment block, GetLastError returns ERROR_ENVVAR_NOT_FOUND.

Requirements

• Client Requires Windows Vista, Windows XP, or Windows 2000 Professional.
• Server Requires Windows Server 2008, Windows Server 2003, or Windows 2000 Server.
• Header Declared in Winbase.h; include Windows.h.
• Library Use Kernel32.lib.
• DLL Requires Kernel32.dll.
• Unicode Implemented as GetEnvironmentVariableW (Unicode) and GetEnvironmentVariableA (ANSI).

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Notebook exported on Monday, 7 July 2008, 18:56:50 PM Eastern Daylight Time