GetEnvironmentVariable function

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

Syntax

DWORD GetEnvironmentVariable(
  LPCTSTR lpName,
  LPTSTR  lpBuffer,
  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, including the null-terminating character, 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 and the contents of lpBuffer are undefined.

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.

Remarks

This function can retrieve either a system environment variable or a user environment variable.

Examples

For an example, see Changing Environment Variables.

Requirements

   
Minimum supported client Windows XP [desktop apps | UWP apps]
Minimum supported server Windows Server 2003 [desktop apps | UWP apps]
Target Platform Windows
Header winbase.h (include Windows Server 2003, Windows Vista, Windows 7, Windows Server 2008 Windows Server 2008 R2, Windows.h)
Library Kernel32.lib
DLL Kernel32.dll

See Also

Environment Variables

GetEnvironmentStrings

SetEnvironmentVariable