linux下常用的基本设置与操作C语言实现

获取系统时间

int getlocaltime(struct tm *time)
{
    struct timeval tv;
    time_t second;
    struct tm *temp;

    gettimeofday(&tv, NULL);
    second = tv.tv_sec;

    temp = localtime(&second);
    temp->tm_year += ;
    temp->tm_mon += ;
    memcpy(time, temp,sizeof(struct tm));

    ;
}

设置系统时间

int setlocaltime(struct tm *tm)
{
    time_t timesec;
    struct timeval tv;
    struct tm temptm;

    memcpy(&temptm,tm,sizeof(temptm));
    temptm.tm_year = tm->tm_year - ;
    temptm.tm_yday = ;
    temptm.tm_isdst = -;                /* Be sure to recheck dst. */
    timesec = mktime(&temptm);
    tv.tv_sec = timesec;
    tv.tv_usec    = ;
    settimeofday(&tv,);        //设置系统时间
    ;
}

获取IP地址

void getip(unsigned char* ip_buf,char * name)
{
    struct ifreq temp;
    struct sockaddr_in *myaddr;
    ;
    ;
    strcpy(temp.ifr_name, name);

    ))<)
    {
        return NULL;
    }
    ret = ioctl(fd, SIOCGIFADDR, &temp);
    close(fd);
    )
        return NULL;
    myaddr = (struct sockaddr_in *)&(temp.ifr_addr);
    strcpy(ip_buf, inet_ntoa(myaddr->sin_addr));
    printf("getip:%s\n",ip_buf);

} 

设置IP地址

int setip(char* ip)
{
    struct ifreq temp;
    struct sockaddr_in *addr;
    ;
    ;
    strcpy(temp.ifr_name, "eth0");

    ))<)
    {
        ;
    }

    addr = (struct sockaddr_in *)&(temp.ifr_addr);
    addr->sin_family = AF_INET;
    addr->sin_addr.s_addr = inet_addr(ip);
    ret = ioctl(fd, SIOCSIFADDR, &temp);
    close(fd);
    )
        ;
    ;
} 

检查网线是否连接

int check_nic(void)
{
    struct ifreq ifr;
    );  

    strcpy(ifr.ifr_name, "eth0");
    )
    {
        close(skfd);
        ;
    } 

    if(ifr.ifr_flags & IFF_RUNNING)
    {
        printf("link up\n");
        close(skfd);
        ; // 网卡已插上网线
    }
    else
    {
        printf("link down\n");
        close(skfd);
        ;
    }
}  

读取本机MAC地址

int read_mac(unsigned char *buf,char *name)
{
    int sock;
    int ret;
    struct ifreq ifr; 

    sock = socket(AF_INET, SOCK_DGRAM, );
    )
    {
        perror("socket error");
        ;
    } 

    memset(&ifr, , sizeof(ifr));
    strcpy(ifr.ifr_name, name);
    ifr.ifr_name[] = '\0';

    ret = ioctl(sock,SIOCGIFHWADDR,&ifr);
    )
    {
        memcpy(buf, ifr.ifr_hwaddr.sa_data, );
        printf("HW address is: %02x:%02x:%02x:%02x:%02x:%02x \n",
        (unsigned ], (unsigned ], (unsigned ],
        (unsigned ], (unsigned ], (unsigned ]);

    }
    else
    {
        perror("ioctl error!\n");
    }

    close(sock);

    return ret;
}

判断文件是否存在

int is_file_exist(const char *file_path)
{
    if(file_path == NULL)
        ;
    )
        ;
    ;
}