如何在c中设置UDP套接字中的源端口?
有人能告诉我如何在UDP套接字中设置源端口地址吗?。我的客户端应用程序需要将数据包从57002端口发送到服务器端口58007。。使用地址和端口号。如何在c中设置UDP套接字中的源端口?,c,sockets,udp,udpclient,C,Sockets,Udp,Udpclient,有人能告诉我如何在UDP套接字中设置源端口地址吗?。我的客户端应用程序需要将数据包从57002端口发送到服务器端口58007。。使用地址和端口号。#包括 struct sockaddr_in sa; int ret, fd; memset(&sa, 0, sizeof(struct sockaddr_in)); sa.sin_family = AF_INET; sa.sin_port = htons(LOCAL_PORT); sa.sin_addr.s_addr = ine
#包括
struct sockaddr_in sa;
int ret, fd;
memset(&sa, 0, sizeof(struct sockaddr_in));
sa.sin_family = AF_INET;
sa.sin_port = htons(LOCAL_PORT);
sa.sin_addr.s_addr = inet_addr(LOCAL_IP_ADDRESS);
ret = bind(fd, (struct sockaddr *)&sa, sizeof(struct sockaddr));
#包括
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#包括
#包括
#包括
#定义DST_端口58007
#定义SRC_端口57002
#定义IP“127.0.0.1”
int main(int argc,char*argv[]){
地址中的结构sockaddr\u,srcaddr;
int-fd;
char message[]=“你好,世界!”;
if((fd=套接字(AF_INET,SOCK_DGRAM,0))<0){
佩罗(“插座”);
出口(1);
}
memset(&addr,0,sizeof(addr));
addr.sin_family=AF_INET;
addr.sin\u addr.s\u addr=inet\u addr(IP);
地址sin_端口=htons(DST_端口);
memset(&srcadr,0,sizeof(srcadr));
srcadr.sin_family=AF_INET;
srcadr.sin\u addr.s\u addr=htonl(INADDR\u ANY);
srcadr.sin_port=htons(SRC_port);
if(bind(fd,(struct sockaddr*)&srcaddr,sizeof(srcaddr))<0{
佩罗(“绑定”);
出口(1);
}
而(1){
如果(发送到(fd,消息,消息大小),0,(结构sockaddr*)和addr,
sizeof(地址))<0){
perror(“sendto”);
出口(1);
}
睡眠(1);
}
返回0;
}
手动页面链接有一个示例。这里是另一个如果源端口未绑定,如何拾取随机源端口以及如何控制/指定范围?
struct sockaddr_in servaddr,cliaddr;
sockfd=socket(AF_INET,SOCK_DGRAM,0);
servaddr.sin_family = AF_INET;
servaddr.sin_addr.s_addr=inet_addr(argv[1]);
servaddr.sin_port=htons(32000); //destination port for incoming packets
cliaddr.sin_family = AF_INET;
cliaddr.sin_addr.s_addr= htonl(INADDR_ANY);
cliaddr.sin_port=htons(33000); //source port for outgoing packets
bind(sockfd,(struct sockaddr *)&cliaddr,sizeof(cliaddr));
use sendto with servaddr
use recvfrom with cliaddr
if u check wireshark u will see source port as 33000 and destination port as 32000 for sendto operation
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#define DST_PORT 58007
#define SRC_PORT 57002
#define IP "127.0.0.1"
int main(int argc, char *argv[]) {
struct sockaddr_in addr, srcaddr;
int fd;
char message[] = "Hello, World!";
if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
perror("socket");
exit(1);
}
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = inet_addr(IP);
addr.sin_port = htons(DST_PORT);
memset(&srcaddr, 0, sizeof(srcaddr));
srcaddr.sin_family = AF_INET;
srcaddr.sin_addr.s_addr = htonl(INADDR_ANY);
srcaddr.sin_port = htons(SRC_PORT);
if (bind(fd, (struct sockaddr *) &srcaddr, sizeof(srcaddr)) < 0) {
perror("bind");
exit(1);
}
while (1) {
if (sendto(fd, message, sizeof(message), 0, (struct sockaddr *) &addr,
sizeof(addr)) < 0) {
perror("sendto");
exit(1);
}
sleep(1);
}
return 0;
}