我正在尝试通过 udp 套接字发送一组十六进制值,但我不能只接收第一个字节 0x22。有什么问题??提前致谢!!!
PD:如何使用十六进制值打印数组?
/* UDP client in the internet domain */
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <signal.h>
#include <time.h>
void error(const char *);
int main()
{
int sock, n;
unsigned int length;
struct sockaddr_in server;
struct hostent *hp;
char buffer[13]={0x22,0x00,0x0d,0xf4,0x35,0x31,0x02,0x71,0xa7,0x31,0x88,0x80,0x00};
hp = gethostbyname("127.0.0.1");
if (hp==0) error("Unknown host");
sock= socket(AF_INET, SOCK_DGRAM, 0);
if (sock < 0) error("socket");
server.sin_family = AF_INET;
bcopy((char *)hp->h_addr,
(char *)&server.sin_addr,
hp->h_length);
server.sin_port = htons(atoi("6666"));
length=sizeof(struct sockaddr_in);
while (1) {
n=sendto(sock,buffer,strlen(buffer),0,(const struct sockaddr *)&server,length);
if (n < 0) error("Sendto");
printf("Sending Packet...\n");
sleep(1);
}
close(sock);
return 0;
}
void error(const char *msg)
{
perror(msg);
exit(0);
}
最佳答案
那是因为你正在使用 strlen(buffer) 而 buffer[1] 是 Null
使用 sizeof(buffer)
代替 strlen(buffer)
关于c - 通过 UDP 套接字发送十六进制值,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/11702673/