网络编程文件传输

1，文件发送端

2，文件接收端

文件发送端：

#include <iostream>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>//结构体addrinfo, in_addr
#include <netinet/in.h>
#include <arpa/inet.h>
#include <fcntl.h>
#include <unistd.h>
int main(int argc, char* argv[]){
  char* service = "12345";
  addrinfo hints, *res0, *res;
  int err;
  int sock;
  int fd;
  char buf[65536];
  int n, ret;
  if(argc != 3){return 1;}
  fd = open(argv[2], O_RDONLY);
  if(fd < 0){
    perror("open");
    return 1;
  }
  memset(&hints, 0, sizeof(hints));
  hints.ai_socktype = SOCK_STREAM;
  hints.ai_family = PF_UNSPEC;//既适应IPv4又适应IPv6
  if((err = getaddrinfo(argv[1], service, &hints, &res0)) != 0){
    printf("error %d:%s\n", err, gai_strerror(err));
    return 1;
  }
  for(res = res0; res != NULL; res = res->ai_next){
    sock = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
    if(sock < 0){continue;}
    if(connect(sock, res->ai_addr, res->ai_addrlen) != 0){
      close(sock);
      continue;
    }
    break;
  }
  freeaddrinfo(res0);
  if(res == NULL){
    printf("failed\n");
    return 1;
  }
  while((n = read(fd, buf, sizeof(buf))) > 0){
    ret = write(sock, buf, n);
    if(ret < 1){
      perror("write");
      break;
    }
  }
  close(sock);
  return 0;
}

github源代码

发送端的执行方式：

./a.out 127.0.0.1 text.txt

文件接收端

#include <iostream>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>//结构体addrinfo, in_addr
#include <netinet/in.h>
#include <arpa/inet.h>
#include <fcntl.h>
#include <unistd.h>
int main(int argc, char* argv[]){
  int sock0;
  sockaddr_in client;
  socklen_t len;
  int sock;
  addrinfo hints, *res;
  int err;
  int fd;
  int n, ret;
  char buf[65536];
  if(argc != 2){return 1;}
  fd = open(argv[1], O_WRONLY | O_CREAT, 0600);
  memset(&hints, 0, sizeof(hints));
  hints.ai_family = AF_INET;
  hints.ai_flags = AI_PASSIVE;
  hints.ai_socktype = SOCK_STREAM;
  err = getaddrinfo(NULL, "12345", &hints, &res);
  if(err != 0){
    printf("error %d:%s\n", err, gai_strerror(err));
    return 1;
  }
  sock0 = socket(res->ai_family, res->ai_socktype, 0);
  bind(sock0, res->ai_addr, res->ai_addrlen);
  freeaddrinfo(res);
  listen(sock0, 5);
  len = sizeof(client);
  sock = accept(sock0, (sockaddr*)&client, &len);
  while((n = read(sock, buf, sizeof(buf))) > 0){
    ret = write(fd, buf, n);
  }
  close(sock);
  close(sock0);
  return 0;
}