#include <sys/socket.h> 
#include <sys/types.h> 
#include <netinet/in.h> 
#include <arpa/inet.h> 
#include <errno.h> 
#include <fcntl.h> 
#include <sys/un.h> 
#include <pthread.h> 
#include <cstring> 
#include <cstdio> 
#include <unistd.h> 
#include <signal.h> 
 
#define filename "test.socket" 
 
void setnonblocking(int fd) 
{ 
  fcntl(fd, F_SETFL, fcntl(fd, F_GETFL) | O_NONBLOCK); 
} 
 
void *client_func(void *arg) 
{ 
  sleep(3); 
  int fd = socket(AF_UNIX, SOCK_STREAM, 0); 
  setnonblocking(fd); 
  sockaddr_un un; 
  memset(&un, 0, sizeof(un)); 
  un.sun_family = AF_UNIX; 
  sprintf(un.sun_path, "file_%d.socket", (int)getpid()); 
  unlink(un.sun_path); 
  socklen_t len = sizeof(un); 
  bind(fd, (sockaddr *)&un, sizeof(un)); 
  strcpy(un.sun_path, filename); 
  int ret = connect(fd, (sockaddr *)&un, len); 
  if (ret == -1) 
  { 
    printf("connect server failed...\n"); 
    close(fd); 
    return NULL; 
  } 
  char buf[256]; 
  memset(buf, 0, sizeof(buf)); 
  strcpy(buf, "hello world"); 
  int n = send(fd, buf, strlen(buf)+1, 0); 
  printf("send data, %d bytes..\n", n); 
  sleep(5); 
  close(fd); 
 
  return NULL; 
} 
 
int main() 
{ 
  unlink(filename);   
  signal(SIGPIPE, SIG_IGN); 
  int fd = socket(AF_UNIX, SOCK_STREAM, 0); 
  int yes = 1; 
  setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)); 
  setnonblocking(fd); 
  sockaddr_un un; 
  memset(&un, 0, sizeof(un)); 
  un.sun_family = AF_UNIX; 
  strcpy(un.sun_path, filename); 
  bind(fd, (sockaddr *)&un, sizeof(un)); 
  listen(fd, 100); 
   
  pthread_t pid; 
  pthread_create(&pid, NULL, client_func, NULL); 
 
  sockaddr_un uu; 
  socklen_t len = sizeof(uu);  
  while (true) 
  { 
    memset(&uu, 0, len); 
    int newfd = accept(fd, (sockaddr *)&uu, &len);  
    if (newfd != -1) 
    { 
      setnonblocking(newfd); 
      printf("newfd = %d, path = %s\n", newfd, uu.sun_path); 
      char buf[512]; 
      memset(buf, 0, sizeof(buf)); 
      int n = recv(newfd, buf, 512,0); 
      printf("recv %d bytes, contents is %s\n", n, buf); 
    } 
    usleep(100000); 
  } 
   
  close(fd); 
 
  return 0; 
}