test1.c

使用select实现的UNIX/Linux环境下的TCP聊天程序

#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>
#include <errno.h>

void signal_handler(int s);

int main(int argc, char **argv)
{
  int n;

  signal(SIGINT, signal_handler);

  for (;;)
  {
    //int select(int n, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout);
    if ((n = select(1, NULL, NULL, NULL, NULL)) < 0)
    {
      if (errno == EINTR)
      {
	fprintf(stdout, "Interrupted by a signal, retry.\n");
	continue;
      }
      else
      {
	fprintf(stderr, "Other error: %s, exit.\n", strerror(errno));
	exit(1);
      }
    }
    else if (n == 0)
    {
      fprintf(stdout, "timeout ...\n");
    }
    else
    {
      // TODO:
    }
  }

  return 0;
}

void signal_handler(int s)
{
  fprintf(stdout, "Caught signal %d\n", s);
}