GetEnvironmentVariable

　　GetEnvironmentVariable函式從調用該函式的進程的環境變數中,返回指定的變數名的值,該值是一個以零結尾的字元串指針.

　
DWORD GetEnvironmentVariable(
LPCTSTR lpName, // address of environment variable name
LPTSTR lpBuffer, // address of buffer for variable value
DWORD nSize // size of buffer, in characters
);
參數:
lpName:要獲取值的變數名字元串指針.
lpBuffer:接收變數值的字元串指針
nSize:接收變數值的記憶體大小.
返回值:
如果函式成功執行,則返回值是寫入字元緩衝區的字元數量,但不包含'\0'字元.
如果沒有找到所指的變數,則返回零.
如果字元緩衝區的大小小於變數值的長度,返回值為緩衝區的大小.
速查:
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: unsupported.
Header: declared in winbase.h.
Import Library: Use kernel32.lib.
Unicode: Implemented as Unicode and ANSI versions on Windows NT.
另請參閱:
Processes and Threads Overview, Process and Thread Functions, GetEnvironmentStrings, SetEnvironmentVariable