做网站什么费用排名优化关键词公司

1>操控机械臂：

通过w(红色臂角度增大)s（红色臂角度减小）
d（蓝色臂角度增大）a（蓝色臂角度减小）按键控制机械臂

源代码：

#include <myhead.h>
#define minStep 10 //最小偏移角度#define SER_IP "10.168.1.116" //服务器ip
#define SER_PORT 8888         //服务器端口号#define CLI_IP "10.168.1.111 " //客户端IP
#define CLI_PORT 9999          //客户端端口号char scanKeyboard();                                          //从键盘获取控制符
void r_angleUp(int fd, char buf[], int buf_size, char skb);   //红色臂向右偏移
void r_angleDown(int fd, char buf[], int buf_size, char skb); //红色臂向左偏移
void b_angleUp(int fd, char buf[], int buf_size, char skb);   //蓝色色臂向右偏移
void b_angleDown(int fd, char buf[], int buf_size, char skb); //蓝色臂向左偏移int main(int argc, const char *argv[])
{//1、创建用于通信的套接字文件描述符int cfd = socket(AF_INET, SOCK_STREAM, 0);if (cfd == -1){perror("socket error");return -1;}printf("cfd = %d\n", cfd); //3//2、绑定（非必须）//2.1 填充地址信息结构体struct sockaddr_in cin;cin.sin_family = AF_INET;cin.sin_port = htons(CLI_PORT);cin.sin_addr.s_addr = inet_addr(CLI_IP);//2.2 绑定if (bind(cfd, (struct sockaddr *)&cin, sizeof(cin)) == -1){perror("bind error");return -1;}printf("bind success\n");//3、连接服务器//3.1填充要连接的服务器地址信息结构体struct sockaddr_in sin;sin.sin_family = AF_INET;                //地址族sin.sin_port = htons(SER_PORT);          //端口号sin.sin_addr.s_addr = inet_addr(SER_IP); //ip地址//3.2 连接服务器if (connect(cfd, (struct sockaddr *)&sin, sizeof(sin)) == -1){perror("connect error");return -1;}printf("connect success\n");//4、数据收发char rbuf[5] = {0xff, 0x02, 0x00, 0x00, 0xff};unsigned char bbuf[5] = {0xff, 0x02, 0x01, 0x00, 0xff};//发送给服务器当做初始值send(cfd, rbuf, sizeof(rbuf), 0);sleep(1);send(cfd, bbuf, sizeof(bbuf), 0);printf("请键入W、S、A、D进行控制：");while (1){char skb = scanKeyboard();if (skb == 27)printf("\n请键入W、S、A、D进行控制(键入Q退出控制！)：\n");switch (skb){case 'W':case 'w':{int buf_size1 = sizeof(rbuf);r_angleUp(cfd, rbuf, buf_size1, skb);}break;case 'S':case 's':{int buf_size1 = sizeof(rbuf);r_angleDown(cfd, rbuf, buf_size1, skb);}break;case 'D':case 'd':{int buf_size2 = sizeof(bbuf);b_angleUp(cfd, bbuf, buf_size2, skb);}break;case 'A':case 'a':{int buf_size2 = sizeof(rbuf);b_angleDown(cfd, bbuf, buf_size2, skb);}break;case 'Q':{printf("\n控制已结束\n");return -1;}break;}}//5、关闭套接字close(cfd);return 0;
}char scanKeyboard()
{//终端有三种工作模式：规范模式、非规范模式、原始模式//非规范模式：所有输入时即时有效的，不需要用户另外输入行结束符char in;//定义两个termios结构体变量struct termios new_settings;    //保存用于操作的终端属性struct termios stored_settings; //保存当前的终端属性,以便之后恢复//把标准输入的状态存储在终端配置参数stored_settings中tcgetattr(0, &stored_settings);//把当前终端属性的副本赋值给new_settings，准备对其进行修改。new_settings = stored_settings;//修改new_settings的c_lflag字段，关闭规范模式（ICANON）。//在非规范模式下，输入是即时的，不需要按回车键。new_settings.c_lflag &= (~ICANON);//设置new_settings的VTIME为0。//非规范模式下读取输入时不使用超时。new_settings.c_cc[VTIME] = 0; //非规范模式读取时的超时时间--VTIME//tcgetattr(0, &stored_settings);//在非规范模式下读取输入时至少需要读取1个字符才能返回new_settings.c_cc[VMIN] = 1; //非规范模式读取时的最小字符数--VMIN//将标准输入的属性设置为new_settings，TCSANOW参数指示更改应立即生效，不等待数据传输完成。tcsetattr(0, TCSANOW, &new_settings); //不等数据传输完毕就立即改变属性--TCSANOWin = getchar();//读取完字符后，恢复标准输入的原始属性tcsetattr(0, TCSANOW, &stored_settings);return in;
}void r_angleUp(int fd, char buf[], int buf_size, char skb)
{if (skb != 27) //skb==ECS时退出控制{buf[3] += minStep; //每次操作的角度偏移minStep度if (buf[3] >= 90){buf[3] = 90;}send(fd, buf, buf_size, 0);}return;
}
void r_angleDown(int fd, char buf[], int buf_size, char skb)
{if (skb != 27){buf[3] -= minStep;if (buf[3] <= -90){buf[3] = -90;}send(fd, buf, buf_size, 0);}return;
}
void b_angleUp(int fd, char buf[], int buf_size, char skb)
{if (skb != 27){buf[3] += minStep;if (buf[3] >= 180){buf[3] = 180;}send(fd, buf, buf_size, 0);}return;
}
void b_angleDown(int fd, char buf[], int buf_size, char skb)
{if (skb != 27){buf[3] -= minStep;if (buf[3] <= 0){buf[3] = 0;}send(fd, buf, buf_size, 0);}return;
}

效果展示：

2>基于UDP的TFTP文件传输

源代码:

#include <myhead.h>
#define SER_IP "10.168.1.116"
#define SER_PORT 69
#define MAXSIZE 1024
#define FILESIZE 128
enum mode_opt
{READ = 1,WRITE = 2,DATA = 3,ACK = 4,ERR = 5
};void request_WR(char pack[], int pack_size, char *name, int mode, int *packlen)
{bzero(pack, pack_size);char *p = pack;short int *p1 = (short int *)p;*p1 = htons(mode);           //设置操作码char *p2 = (char *)(p1 + 1); //**********strcpy(p2, name);            //文件名char *p4 = p2 + strlen(p2) + 1;strcpy(p4, "octet");                    //模式位*packlen = 4 + strlen(p2) + strlen(p4); //请求包的大小
}int download(int cfd, struct sockaddr_in sin, char *name)
{char pack[MAXSIZE] = "";int packlen = 0;//组件协议包：下载请求request_WR(pack, sizeof(pack), name, READ, &packlen);sendto(cfd, pack, packlen, 0, (struct sockaddr *)&sin, sizeof(sin));int rcvlen = 0;int fd = -1;if ((fd = open(name, O_WRONLY | O_CREAT | O_TRUNC, 0664)) == -1){perror("open error");close(fd);return -1;}//添加了对块编号的检查和管理unsigned short expected_block_num = 1;char data[MAXSIZE] = "";socklen_t socklen = sizeof(sin);while (1){//收取服务器发来的数据包rcvlen = recvfrom(cfd, data, sizeof(data), 0, (struct sockaddr *)&sin, &socklen);if (rcvlen == -1){perror("recv error");return -1;}short int *p1_data = (short int *)data;short code = ntohs(*p1_data);short block_num = ntohs(*(p1_data + 1));if (code == DATA){if (block_num == expected_block_num) //只有当接收到的数据包的块编号符合预期时，才会写入文件并发送ACK{write(fd, data + 4, rcvlen - 4);char ack[4];*(short *)ack = htons(ACK);*(short *)(ack + 2) = htons(block_num); // 确认收到的块编号sendto(cfd, ack, 4, 0, (struct sockaddr *)&sin, sizeof(sin));if (rcvlen < 516) // 如果接收到的数据包小于516字节，表示是最后一个数据包{printf("下载完成\n");break;}expected_block_num++;}}else if (code == ERR){printf("ERROR:%d\n", block_num); // block_num在这里作为错误码close(fd);return -1; // 返回错误码}}close(fd);return 0;
}
int upload(int cfd, struct sockaddr_in sin, char *name)
{char packet[MAXSIZE] = "";int packlen = 0;request_WR(packet, sizeof(packet), name, WRITE, &packlen);sendto(cfd, packet, packlen, 0, (struct sockaddr *)&sin, sizeof(sin));int fd = -1;if ((fd = open(name, O_RDONLY)) == -1){perror("open error");return -1;}char buf[MAXSIZE] = "";socklen_t socklen = sizeof(sin);int rcvlen = recvfrom(cfd, buf, sizeof(buf), 0, (struct sockaddr *)&sin, &socklen);short int *p1_data = (short int *)buf;提取ACK的操作码short code = ntohs(*p1_data);//提取ACK的块编号unsigned short block_num = ntohs(*(p1_data + 1));if (code != ACK || block_num != 0){printf(" ACK  or block error\n");close(fd);return -1;}unsigned short send_block_num = 1; // 设置发送数据包的块编号while (1){bzero(buf, sizeof(buf));int num = read(fd, buf + 4, 512);if (num < 0){perror("read error");close(fd);return -1;}// 构造数据包头部（操作码和块编号）*(short *)packet = htons(DATA);                 // 设置操作码为DATA*(short *)(packet + 2) = htons(send_block_num); // 设置数据块编号memcpy(packet + 4, buf + 4, num);               // 复制文件数据到数据包// 发送数据包sendto(cfd, packet, num + 4, 0, (struct sockaddr *)&sin, socklen);// 等待ACKrcvlen = recvfrom(cfd, buf, 4, 0, (struct sockaddr *)&sin, &socklen);if (rcvlen < 4){perror("recv ACK error");close(fd);return -1;}p1_data = (short int *)buf;code = ntohs(*p1_data);            // 提取操作码block_num = ntohs(*(p1_data + 1)); // 提取块编号// 检查ACK的块编号是否与发送的数据包匹配if (code != ACK || block_num != send_block_num){printf("ACK  or block error\n");close(fd);return -1;}if (num < 512) // 如果读取的数据小于512字节，表示文件已经发送完毕{printf("上传完毕\n");break;}send_block_num++; // 准备下一个数据块的编号}close(fd);return 0;
}
int main(int argc, char const *argv[])
{printf("\t\t*************************\n");printf("\t\t*********1.下载**********\n");printf("\t\t*********2.上传**********\n");printf("\t\t*********3.退出**********\n");printf("\t\t*************************\n");if (argc < 2){printf("请输入IP\n");return -1;}int choice;scanf("%d", &choice);getchar();char name[FILESIZE];int cfd = socket(AF_INET, SOCK_DGRAM, 0);int reuse = 1;if (setsockopt(cfd, SOL_SOCKET, SO_REUSEADDR, &reuse, sizeof(reuse)) == -1){perror("setsockopt error");return -1;}printf("端口号快速重用成功\n");struct sockaddr_in sin;sin.sin_family = AF_INET;sin.sin_port = htons(SER_PORT);sin.sin_addr.s_addr = inet_addr(SER_IP);socklen_t socklen = sizeof(sin);switch (choice){case 1:{printf("输入下载的文件:");scanf("%s", name);download(cfd, sin, name);}break;case 2:{printf("输入上传的文件:");scanf("%s", name);upload(cfd, sin, name);}break;case 3:{return 0;}break;default:{printf("error choice\n");}break;}close(cfd);return 0;
}

效果展示: