FreeRTOS 任務句柄（詳解）

BaseType_t xTaskCreate(	TaskFunction_t pxTaskCode,
		        const char * const pcName,/*lint !e971 Unqualified char types are allowed for strings and single characters only. */
			const configSTACK_DEPTH_TYPE usStackDepth,
			void * const pvParameters,
			UBaseType_t uxPriority,
			TaskHandle_t * const pxCreatedTask )//任務句柄函數原型

xReturned = xTaskCreate(
                    vTaskCode,       /* Function that implements the task. */
                    "NAME",          /* Text name for the task. */
                    STACK_SIZE,      /* Stack size in words, not bytes. */
                    ( void * ) 1,    /* Parameter passed into the task. */
                    tskIDLE_PRIORITY,/* Priority at which the task is created. */
                    &xHandle );      /* Used to pass out the created task's handle.//任務句柄函數原型 */

• 最後一個參數是任務句柄參數（簡稱：TCB）TaskControlBlock
• 翻譯如下：用於傳遞創建的任務句柄
• 估計看到這也不知道啥意思，請往下看 TaskHandle_t 任務句柄函數指針的定義

struct tskTaskControlBlock; /* 原型 The old naming convention is used 
to prevent breaking kernel aware debuggers. */
typedef struct tskTaskControlBlock* TaskHandle_t;/*重新定義了*/

• 任務句柄的源碼  （條件編譯去掉了，太長，畫重點）

/*
 * Task control block.  A task control block (TCB) is allocated for each task,
 * and stores task state information, including a pointer to the task's context
 * (the task's run time environment, including register values)
 */
typedef struct tskTaskControlBlock 			/* The old naming convention is used to prevent breaking kernel aware debuggers. */
{
	volatile StackType_t	*pxTopOfStack;	/*< Points to the location of the last item placed on the tasks stack.  THIS MUST BE THE FIRST MEMBER OF THE TCB STRUCT. */

	ListItem_t	xStateListItem;	/*任務狀態列表< The list that the state list item of a task is reference from denotes the state of that task (Ready, Blocked, Suspended ). */
	ListItem_t	xEventListItem;		/*任務事件列表< Used to reference a task from an event list. */
	UBaseType_t	uxPriority;			/*優先級< The priority of the task.  0 is the lowest priority. */
	StackType_t	*pxStack;			/*棧指針< Points to the start of the stack. */
	char		pcTaskName[ configMAX_TASK_NAME_LEN ];/*< Descriptive name given to the task when created.  Facilitates debugging only. */ /*lint !e971 Unqualified char types are allowed for strings and single characters only. */
} tskTCB;//說明任務句柄包含創建任務的所有狀態，說成任務的身份證最爲合適，想刪除，直接抹掉身份證就可以了

• 說明任務句柄包含創建任務的所有狀態，說成任務的身份證最爲合適，想刪除，直接抹掉身份證就可以了

/*
 * Task control block.  A task control block (TCB) is allocated for each task,
 * and stores task state information, including a pointer to the task's context
 * (the task's run time environment, including register values)
 *任務控制塊。 爲每個任務分配一個任務控制塊（TCB），
 *並存儲任務狀態信息，包括指向任務上下文的指針
 *（任務的運行時環境，包括寄存器值）
 */

• 任務句柄，在FreeRTOS又叫任務控制塊，包含創建任務的所有信息，所有刪除任務就可以這樣來做

/* 任務創建後，用刪除任務句柄來刪除此任務The task was created.  Use the task's handle to delete the task. */
vTaskDelete( xHandle );