关于RT-Thread信号的使用

发布于 2024-04-10 15:20:04 浏览：296 订阅该版

在使用信号时，我同时在两个线程中安装该信号，但是只有第一个线程可以触发这个信号，是为什么呢？

```c
/*
 * Copyright (c) 2006-2021, RT-Thread Development Team
 *
 * Change Logs:
 * Date           Author         Notes
 * 2021-08-20     weidongshan    first version
 */

#include <rtthread.h>
#include <rtdevice.h>
#include <board.h>

#define THREAD_PRIORITY         15  //设置线程优先级
#define THREAD_STACK_SIZE       512 //设置线程栈大小
#define THREAD_TIMESLICE        15  //设置线程时间片大小

static struct rt_thread *thread1;   //定义线程1句柄指针
static struct rt_thread *thread2;   //定义线程2句柄指针

/* 线程1的信号处理函数 */
void thread1_signal_handler(int sig)
{
    rt_kprintf("Thread1 received signal %d\n", sig);
}

void thread2_signal_handler(int sig)
{
    rt_kprintf("Thread2 received signal %d\n", sig);
}

/* 线程1的入口函数 */
static void thread1_entry(void *parameter)
{
	const char *thread_name = parameter;
	
	/* 打印线程的信息 */
	rt_kprintf(thread_name);
	
	/* 安装信号,自定义处理函数 */
	rt_signal_install(SIGUSR1, thread1_signal_handler);
	
	/* 解除阻塞 */
	rt_signal_unmask(SIGUSR1);
	
	while(1)
	{		
		rt_thread_mdelay(500);
	}
}

/* 线程2的入口函数 */
static void thread2_entry(void *parameter)
{
	const char *thread_name = parameter;
	
	/* 打印线程的信息 */
	rt_kprintf(thread_name);
	
	/* 安装信号,系统默认处理 */
	rt_signal_install(SIGUSR1, thread2_signal_handler);
	
	/* 解除阻塞 */
	rt_signal_unmask(SIGUSR1);
	
	while(1)
	{		
		rt_thread_mdelay(500);
	}
}

static const char *thread1_name = "Thread1 run\r\n";
static const char *thread2_name = "Thread2 run\r\n";

int main(void)
{
	/* 创建动态线程thread1，优先级为 THREAD_PRIORIT = 15 */
    thread1 = rt_thread_create("thread1",          //线程名字
                            thread1_entry,         //入口函数
							(void *)thread1_name,  //入口函数参数
                            THREAD_STACK_SIZE,     //栈大小
                            THREAD_PRIORITY,       //线程优先级
				            THREAD_TIMESLICE);     //线程时间片大小

/* 判断创建结果,再启动线程1 */
    if (thread1 != RT_NULL)
        rt_thread_startup(thread1);

/* 创建动态线程thread2，优先级为 THREAD_PRIORIT = 15 */
    thread2 = rt_thread_create("thread2",          //线程名字
                            thread2_entry,         //入口函数
							(void *)thread2_name,  //入口函数参数
                            THREAD_STACK_SIZE,     //栈大小
                            THREAD_PRIORITY,       //线程优先级
				            THREAD_TIMESLICE);     //线程时间片大小

/* 判断创建结果,再启动线程2 */
    if (thread2 != RT_NULL)
        rt_thread_startup(thread2);

rt_thread_mdelay(100);	
	   
  rt_thread_kill(thread1, SIGUSR1); //向线程1发送信号SIGUSR1
	rt_thread_kill(thread2, SIGUSR1); //向线程1发送信号SIGUSR1
	
			
    return 0;
}

```
![1712733581226.jpg](https://oss-club.rt-thread.org/uploads/20240410/dc2f81174f38b5791dd9a33d97e87bb2.jpg)