我没有找到重复的内容,所以决定进行发布。我们现在开始进入套接字(初学级别)领域,被要求使用
感谢您的时间。
send()
和recv()
函数编写下面的代码,使客户端向服务器发送一条简单消息。然而,不管我尝试了什么,都无法摆脱错误:坏文件描述符
,并且newsockfd
总是返回值-1
。我很困惑,也不知道为什么会出现这种情况。
defs.h
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#define SERV_TCP_PORT 6000
#define SERV_HOST_ADDR "127.0.0.1"
char *pname;
client.c
#include "../defs.h"
#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
main(argc, argv)
int argc;
char *argv[];
{
int sockfd;
struct sockaddr_in serv_addr;
pname=argv[0];
bzero((char*) &serv_addr, sizeof(serv_addr));
serv_addr.sin_family=AF_INET;
serv_addr.sin_addr.s_addr=inet_addr(SERV_HOST_ADDR);
serv_addr.sin_port=htons(SERV_TCP_PORT);
if((sockfd=socket(AF_INET,SOCK_STREAM,0)) < 0) {
printf("client: can't open stream socket\n");
exit(0);
}
if (connect(sockfd,(struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
printf("client: can't connect to server\n");
exit(0);
}
send(sockfd,"1",1,0);
close(sockfd);
exit(0);
}
server.c
#include "../defs.h"
#include <stdio.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <strings.h>
void error(char *msg)
{
perror(msg);
exit(1);
}
main(argc, argv)
int argc;
char *argv[];
{
int sockfd,clilen, childpid;
int newsockfd;
char buff[255];
struct sockaddr_in cli_addr, serv_addr;
if ((sockfd=socket(AF_INET,SOCK_STREAM, 0)) <0) {
printf("server: can't open stream socket\n");
exit(0);
}
bzero((char*) &serv_addr, sizeof(serv_addr));
serv_addr.sin_family=AF_INET;
serv_addr.sin_addr.s_addr=htonl(INADDR_ANY);
serv_addr.sin_port=htons(SERV_TCP_PORT);
if(bind(sockfd, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
printf("server: can't bind local address\n");
exit(0);
}
listen(sockfd, 5);
for ( ; ; ) {
clilen=sizeof(cli_addr);
newsockfd = accept(sockfd, (struct sockaddr *) &cli_addr, &clilen);
printf("%d\n",newsockfd);
if(newsockfd < 0) {
printf("server: accept error\n");
error("ERROR on accept");
exit(0);
}
if((childpid=fork()) <0) {
printf("server: fork error\n");
exit(0);
}
else if (childpid==0) {
close(sockfd);
recv(newsockfd,buff,sizeof(buff),0);
}
close(newsockfd);
}
}
感谢您的时间。