VxWorks任务钩子示例

/* includes */
#include "vxWorks.h"
#include "taskLib.h"
#include "taskHookLib.h"    /* taskHook所对应的库 */

 

/* task function */
void myFunc(void)
{
    int i;
    printf("Hello, I am task %d\n", taskIdSelf()); /* Print task Id */
}

 

/* taskCreatHook */
void myTaskHook(void)
{
    printf("task hook function called\n");
}

 

/* user entry */
void user_start()
{
    taskCreateHookAdd( (FUNCPTR) myTaskHook);
    taskSpawn("myTask", 90, 0x100, 2000, (FUNCPTR) myFunc, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
}

运行输出：
task hook function called
Hello, I am task 14868640

 

  有过Windows钩子（Hook）编程经验的读者应该对其概念并不陌生，Hook作为回调函数，当被挂接后。操作系统发生特定的事情时，将触发这个Hook回调函数的执行。VxWorks也有钩子的概念，不过比Windows要简单许多，主要有taskCreateHook、taskDeleteHook、taskSwitchHookAdd，可以通过如下6个API来添加和删除这三种Hook：
STATUS taskCreateHookAdd (FUNCPTR createHook /* routine to be called when a task is created */ );
STATUS taskCreateHookDelete (FUNCPTR createHook /* routine to be deleted from list */);
STATUS taskSwitchHookAdd (FUNCPTR switchHook /* routine to be called at every task switch */);
STATUS taskSwitchHookDelete (FUNCPTR switchHook /* routine to be deleted from list */);
STATUS taskDeleteHookAdd (FUNCPTR deleteHook /* routine to be called when a task is deleted */);
STATUS taskDeleteHookDelete (FUNCPTR deleteHook /* routine to be deleted from list */);