树莓派CAN通讯(c语言)

【核心代码】

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <net/if.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <linux/can.h>
#include <linux/can/raw.h>

int main()
{
    int ret;
    int s, nbytes;
    struct sockaddr_can addr;
    struct ifreq ifr;
    struct can_frame frame;
    memset(&frame, 0, sizeof(struct can_frame));

    system("sudo ip link set can0 type can bitrate 100000");
    system("sudo ifconfig can0 up");
    printf("this is a can send demo\r\n");

    //1.Create socket <创建接口>
    s = socket(PF_CAN, SOCK_RAW, CAN_RAW);
    if (s < 0) {
        perror("socket PF_CAN failed");
        return 1;
    }

    //2.Specify can0 device <指定can0设备>
    strcpy(ifr.ifr_name, "can0");
    ret = ioctl(s, SIOCGIFINDEX, &ifr);
    if (ret < 0) {
        perror("ioctl failed");
        return 1;
    }

    //3.Bind the socket to can0 <将接口绑定到can0>
    addr.can_family = AF_CAN;
    addr.can_ifindex = ifr.ifr_ifindex;
    ret = bind(s, (struct sockaddr *)&addr, sizeof(addr));
    if (ret < 0) {
        perror("bind failed");
        return 1;
    }

    //4.Disable filtering rules, do not receive packets, only send<禁用筛选规则，不接收数据包，只发送>
    setsockopt(s, SOL_CAN_RAW, CAN_RAW_FILTER, NULL, 0);

    //5.Set send data<设置发送数据>
    frame.can_id = 0x123;
    frame.can_dlc = 8;
    frame.data[0] = 1;
    frame.data[1] = 2;
    frame.data[2] = 3;
    frame.data[3] = 4;
    frame.data[4] = 5;
    frame.data[5] = 6;
    frame.data[6] = 7;
    frame.data[7] = 8;

    printf("can_id  = 0x%X\r\n", frame.can_id);
    printf("can_dlc = %d\r\n", frame.can_dlc);
    int i = 0;
    for(i = 0; i < 8; i  )
        printf("data[%d] = %d\r\n", i, frame.data[i]);

    //6.Send message<发送消息>
    nbytes = write(s, &frame, sizeof(frame));
    if(nbytes != sizeof(frame)) {
        printf("Send Error frame[0]!\r\n");
        system("sudo ifconfig can0 down");
    }

    //7.Close the socket and can0<关闭接口和can0>
    close(s);
    system("sudo ifconfig can0 down");
    return 0;
}