联合访问结构

Question

typedef struct _JOBOBJECT_CPU_RATE_CONTROL_INFORMATION {
  DWORD ControlFlags;
  union {
    DWORD  CpuRate;
    DWORD  Weight;
    struct {
      WORD MinRate;
      WORD MaxRate;
    };
  };
} JOBOBJECT_CPU_RATE_CONTROL_INFORMATION, *PJOBOBJECT_CPU_RATE_CONTROL_INFORMATION;

https://msdn.microsoft.com/en-us/library/windows/desktop/hh448384.aspx

在上面的结构中，如何访问/更改MaxRate？我这样得到ControlFlags：

JOBOBJECT_CPU_RATE_CONTROL_INFORMATION cpu;
cpu.ControlFlags = JOB_OBJECT_CPU_RATE_CONTROL_HARD_CAP;

Answer 1

在我的winnt.h标题副本中，结构定义如下：

typedef struct _JOBOBJECT_CPU_RATE_CONTROL_INFORMATION {
    DWORD ControlFlags;
    union {
        DWORD CpuRate;
        DWORD Weight;
    };
} JOBOBJECT_CPU_RATE_CONTROL_INFORMATION, *PJOBOBJECT_CPU_RATE_CONTROL_INFORMATION;

确实没有MinRate或MaxRate。我的猜测是，它们可能已经在SDK的某个更高版本中添加了（我目前只有VC2013方便）。

了解获取SDK的更新版本。同时，LOWORD(CpuRate)和HIWORD(CpuRate)应该这样做。