翻译一下int thrd_num = *( int * )arg; char buff[BUFFER_SIZE]; printf( "Read thread get data %d\n" , thrd_num ); do { memset( buff , 0 , BUFFER_SIZE ); if ( read( com_fd, buff, BUFFER_SIZE ) > 0 ) { printf("The received words are : %s\n", buff); if(!strncmp( buff , "ok" , 2 ) ) sem_post( &getok ); } } while(strncmp( buff , "quit" , 4 ) );
时间: 2024-01-27 08:04:15 浏览: 26
这段代码是读串口线程的主体函数,用于从串口读取数据并进行处理。首先,代码中的 `int thrd_num = *( int * )arg` 用于获取传入的线程编号,方便调试和区分不同的线程。然后声明了一个字符数组 `buff` 用于存储从串口读取到的数据。接着进入一个循环,每次循环首先清空 `buff` 数组,然后通过 `read` 函数从串口读取数据,如果读取的数据长度大于 0,则输出读取到的数据。如果读取到的数据是字符串 "ok",则调用 `sem_post` 函数将信号量 `getok` 的值加 1,唤醒等待该信号量的线程。最后,如果读取到的数据是字符串 "quit",则退出循环,结束读串口的操作。
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翻译一下并每一行进行注释pthread_t thrd_writecom ; int res; void * thrd_ret; char *test = "Hello!\n"; /* 打开串口 */ if((com_fd = open_port(TARGET_COM_PORT)) < 0) { perror("open_port"); return 1; } /* 初始化串口 */ if(set_com_config(com_fd, 115200, 8, 'N', 1) < 0) { perror("set_com_config"); return 1; } //创建写处理线程 res = pthread_create( &thrd_writecom , NULL , thrd_wcom , (void *)test); if (res != 0) { printf("Create COM read thread failed\n"); exit(res); } printf("Create threads success\n Waiting for threads to finish...\n"); //等待回收写串口线程 res = pthread_join(thrd_writecom, &thrd_ret); if (!res) { printf("COM write Thread joined\n"); } else { printf("COM write Thread join failed\n"); } close(com_fd);
注释已经添加在每一行的末尾。
```c++
pthread_t thrd_writecom; //定义线程ID变量
int res;
void *thrd_ret;
char *test = "Hello!\n"; //定义发送的字符串变量
/* 打开串口 */
if ((com_fd = open_port(TARGET_COM_PORT)) < 0) //打开串口
{
perror("open_port"); //打印错误信息
return 1;
}
/* 初始化串口 */
if (set_com_config(com_fd, 115200, 8, 'N', 1) < 0) //初始化串口
{
perror("set_com_config"); //打印错误信息
return 1;
}
//创建写处理线程
res = pthread_create(&thrd_writecom, NULL, thrd_wcom, (void *)test); //创建线程,指定线程函数和参数
if (res != 0)
{
printf("Create COM write thread failed\n"); //打印错误信息
exit(res);
}
printf("Create threads success\n Waiting for threads to finish...\n"); //输出提示信息
//等待回收写串口线程
res = pthread_join(thrd_writecom, &thrd_ret); //等待线程结束
if (!res)
{
printf("COM write Thread joined\n"); //输出提示信息
}
else
{
printf("COM write Thread join failed\n"); //打印错误信息
}
close(com_fd); //关闭串口
```
这段代码主要是打开并初始化串口,然后创建一个写串口的线程,等待该线程执行完毕后再退出。其中,使用了pthread库中的函数来创建和等待线程。
翻译这段代码并在每一行后注释/* 初始化互斥锁 */ pthread_mutex_init(&mutex, NULL); /* 初始化信号量 */ sem_init( &getok , 0 , 1 ); /* 创建读串口子线程 */ res = pthread_create(&thrd_readcom, NULL, thrd_rcom, &no); if (res != 0) { printf("Create COM read thread failed\n"); exit(res); } printf("Create threads success\n Waiting for threads to finish...\n"); while(1){ res = sem_wait( &getok ); res = pthread_create( &thrd_writecom , NULL , thrd_wcom , (void *)test); } //等待回收读串口线程 res = pthread_join(thrd_readcom, &thrd_ret); if (!res) { printf("COM read Thread joined\n"); } else { printf("COM read Thread join failed\n"); } //等待回收写串口线程 res = pthread_join(thrd_writecom, &thrd_ret); if (!res) { printf("COM write Thread joined\n"); } else { printf("COM write Thread join failed\n"); } //释放互斥锁 pthread_mutex_destroy(&mutex);
/* 初始化互斥锁 */
pthread_mutex_init(&mutex, NULL);
/* 初始化信号量 */
sem_init(&getok, 0, 1);
/* 创建读串口子线程 */
res = pthread_create(&thrd_readcom, NULL, thrd_rcom, &no);
if (res != 0) {
printf("Create COM read thread failed\n");
exit(res);
}
printf("Create threads success\n Waiting for threads to finish...\n");
while (1) {
res = sem_wait(&getok); //等待信号量
res = pthread_create(&thrd_writecom, NULL, thrd_wcom, (void *)test); //创建写串口子线程
}
//等待回收读串口线程
res = pthread_join(thrd_readcom, &thrd_ret);
if (!res) {
printf("COM read Thread joined\n");
} else {
printf("COM read Thread join failed\n");
}
//等待回收写串口线程
res = pthread_join(thrd_writecom, &thrd_ret);
if (!res) {
printf("COM write Thread joined\n");
} else {
printf("COM write Thread join failed\n");
}
//释放互斥锁
pthread_mutex_destroy(&mutex);