文件传送

//接收方
#include <stdio.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <arpa/inet.h>
int main()
{
    int sfd;int cfd; int ffd;
    int r;
    int len;
    char buf[128];
    char filename[100];/*要读取的文件名*/
    struct sockaddr_in dr;
    /*建立服务器socket*/
    sfd = socket(AF_INET,SOCK_STREAM,0);
    if(sfd==-1)printf("socket error:%m\n"),exit(-1);
    printf("建立服务器成功!\n");
    /*绑定IP地址与端口*/
    dr.sin_family = AF_INET;
    dr.sin_port = htons(9988);
    dr.sin_addr.s_addr=inet_addr("192.168.1.162");/*转换成32为网络字节序*/
    r = bind(sfd,(struct sockaddr*)&dr,sizeof(dr));
    if(r==-1)printf("bind faild...\n"),exit(-1);
    printf("bind OK\n");
    /*监听*/
    r = listen(sfd,10);
    if(r==-1)printf("listen:%m\n"),exit(-1);
    printf("listen OK\n");
    /*接收连接*/
    cfd = accept(sfd,0,0);
    if(cfd==-1)printf("accpet error:%m\n"),exit(-1);
    printf("开始接收文件");
    /*接收文件名*/
    r = recv(cfd,&len,sizeof(len),MSG_WAITALL);
    r = recv (cfd,filename,len,MSG_WAITALL);
    filename[len] = 0;
    /*创建文件*/
    ffd = open(filename,O_RDWR|O_CREAT|0666);
    /*循环接收文件数据*/
    while(1)
    {
        r = recv(cfd,&len,sizeof(len),MSG_WAITALL);
        if(len==0)break;
        r = recv(cfd,buf,len,MSG_WAITALL);
        write(ffd,buf,len);
    }
    close(ffd);
    close(cfd);
    close(sfd);
    printf("接收完毕");
    return 0;
}

//传送方
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <netinet/in.h>
#include <string.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <fcntl.h>
int main()
{
    int sfd;/*socket 描述符*/
    int ffd;/*文件描述符*/
    int r;
    int size;
    int len;
    char buf[128];
    struct sockaddr_in dr;
    char filename[]="demo.c";/*文件名*/
    /*建立socket*/
    sfd = socket(AF_INET,SOCK_STREAM,0);
    if(sfd==-1) printf("socket err:%m\n"),exit(-1);
    printf("socket OK...\n");
    /*连接到服务器*/
    dr.sin_family = AF_INET;
    dr.sin_port = htons(9988);
    inet_aton("192.168.1.162",&dr.sin_addr);/*将字符串的IP地址转换成网络序的地址*/
    r = connect(sfd,(struct sockaddr*)&dr,sizeof(dr));/*建立与一个端的连接*/
    if(r==-1) printf("connect err:%m\n"),exit(-1);
    printf("connect OK...\n");
    /*打开文件*/
    ffd = open(filename,O_RDONLY);
    if(ffd==-1)printf("open faild...\n"),exit(-1);
    printf("open file OK...\n");
    /*发送文件名*/
    len = strlen(filename);
    r = send(sfd,&len,sizeof(len),0);
    r = send(sfd,filename,len,0);
    if(r==-1) printf("send err:%m\n"),exit(-1);
    printf("发送数据成功!\n");
    /*循环发送数据*/
    while(1)
    {
        size = read(ffd,buf,128);
        if(size==-1) break;
        if(size==0) break;/*文件末尾*/
        if(size>0)
        {
            /*send()用于向一个已经连接的socket发送数据，如果无错误，返回值为所发送数据的总数，否>则返回SOCKET_ERROR。*/
            r = send(sfd,&size,sizeof(size),0);/*发送数据长度send(描述符,待发送数据缓冲区,缓冲区
数据长度,调用执行方式)*/
            if(r==-1)break;
            r = send(sfd,buf,size,0);/*发送数据*/
            if(r==-1)break;
        }
    }
    size = 0;
    r = send(sfd,&size,sizeof(size),0);
    close(ffd);
    close(sfd);
    printf("OK\n");
    /*读取到文件尾,发送大小为0的数据包*/

    return 0;
}