The GetEnvironmentVariable function retrieves the value of the specified variable from the environment block of the calling process. The value is in the form of a null-terminated string of characters.
DWORD GetEnvironmentVariable(
LPCTSTR lpName, |
// address of environment variable name |
LPTSTR lpBuffer, |
// address of buffer for variable value |
DWORD nSize |
// size of buffer, in characters |
); |
If the function succeeds, the return value is the number of characters stored into the buffer pointed to by lpBuffer, not including the terminating null character.
If the specified environment variable name was not found in the environment block for the current process, the return value is zero.
If the buffer pointed to by lpBuffer is not large enough, the return value is the buffer size, in characters, required to hold the value string and its terminating null character.