如何用C语言从串口读取数据

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <termios.h>

int main() {
    int fd;
    char buffer[256];
    
    // 打开串口
    fd = open("/dev/ttyS0", O_RDWR);
    if (fd == -1) {
        perror("Failed to open serial port");
        return -1;
    }
    
    // 配置串口参数
    struct termios options;
    tcgetattr(fd, &options);
    cfsetispeed(&options, B9600);
    cfsetospeed(&options, B9600);
    options.c_cflag |= (CLOCAL | CREAD);
    options.c_cflag &= ~PARENB;
    options.c_cflag &= ~CSTOPB;
    options.c_cflag &= ~CSIZE;
    options.c_cflag |= CS8;
    tcsetattr(fd, TCSANOW, &options);
    
    // 读取数据
    int nbytes = read(fd, buffer, sizeof(buffer));
    if (nbytes == -1) {
        perror("Failed to read from serial port");
        return -1;
    }
    
    // 处理数据
    printf("Received data: %s\n", buffer);
    
    // 关闭串口
    close(fd);
    
    return 0;
}