SECURITY_ATTRIBUTES，结构包含一个对象的
安全描述符，并指定检索到指定这个结构的句柄是否是可继承的。
简介
这个结构为很多函数创建对象时提供安全性设置。如：
CreateFile，CreatePipe，CreateProcess，
RegCreateKeyEx,RegSaveKeyEx。
n长度
The size, in bytes, of this structure. Set this value to the size of the SECURITY_ATTRIBUTES structure.
为了方便以后对API可能的修改，这个参数定义了整个SECURITY_ATTRIBUTES的结构所占字节数。通常只需要写sizeof(SECURITY_ATTRIBUTES)
描述
lpSecurityDescriptor
A pointer to a security descriptor for the object that controls the sharing of it. If NULL is specified for this member, the object is assigned the default security descriptor of the calling process. This is not the same as granting access to everyone by assigning a NULL discretionary access control list (DACL). The default security descriptor is based on the default DACL of the access token belonging to the calling process. By default, the default DACL in the access token of a process allows access only to the user represented by the access token. If other users must access the object, you can either create a security descriptor with the appropriate access, or add ACEs to the DACL that grants access to a group of users.
Windows Me/98/95: The lpSecurityDescriptor member of this structure is ignored.
操作
A Boolean value that specifies whether the returned handle is inherited when a new process is created. If this member is TRUE, the new process inherits the handle.
资格
Windows NT/2000/XP:Included in Windows NT 3.1 and later.
Header:Declared in Winbase.h; include Windows.h.
转：MSDN