服务器必须在Linux中使用C程序回显客户端发送的消息。我使用的是Ubuntu OS（我不知道这个信息是否有用！）。它第一次起作用。但第二次，它给出了“错误连接”。我尝试更改端口号。但它仍然没有奏效。请指导我。我是初学者。
服务器.c
#include <stdio.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
#include <netinet/in.h>
int main()
{
int sd, sd1, len, confd, n;
struct sockaddr_in ser, cli;
char msg[50];
if((sd = socket(AF_INET,SOCK_STREAM, 0)) < 0)
printf("\nSocket creation error\n");
bzero(&ser, sizeof(ser));
ser.sin_family = cli.sin_family = PF_INET;
ser.sin_port = htons(10000);
ser.sin_addr.s_addr = htonl(INADDR_ANY);
len = sizeof(ser);
if ((bind(sd, (struct sockaddr*)&ser, len)) < 0) {
printf("\nBind Error");
exit(0);
}
if (listen(sd, 2) == 0) {
if ((sd1 = accept(sd, (struct sockaddr*)&ser, &len)) > 0) {
do {
bzero(&msg, 50);
read(sd1, msg, 50);
//int m=(int)msg;
printf("\nMessage from client:%s\n", msg);
write(sd1, msg, strlen(msg));
if(strcmp(msg, "exit") == 0)
break;
} while(strcmp(msg, "exit") != 0);
}
}
}
*强文本*client.c
#include <stdio.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <string.h>
#include <sys/types.h>
#include <unistd.h>
#include <netinet/in.h>
int main()
{
int sd, n, len;
struct sockaddr_in ser, cli;
char text[50];
if ((sd = socket(AF_INET,SOCK_STREAM, 0)) < 0)
printf("\nSocket creation error\n");
bzero(&ser, sizeof(ser));
ser.sin_family = cli.sin_family = PF_INET;
ser.sin_port = htons(10000);
ser.sin_addr.s_addr = htonl(INADDR_ANY);
len = sizeof(ser);
if ((connect(sd, (struct sockaddr*)&ser, len)) < 0) {
printf("\nError connection");
exit(0);
}
while(1) {
strcpy(text, " ");
printf("\nEnter data which is to be sent:");
scanf("%s", text);
write(sd, text, strlen(text));
read(sd, text, 50);
printf("\nEcho msg from server:%s", text);
if (strcmp(text, "exit") == 0)
break;
}
close(sd);
}