text: #include <unistd.h>
  #include <fcntl.h>
  #include <stdio.h>
  
  int main()
  {
  	int fd;
  	int rename_result;
  
  	mode_t mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
  	char *filename = "./rename_org.txt";
  
  	fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, mode);
  
  	rename_result = rename(filename, "rename.txt");
  	if (rename_result == -1)
  	{
  		printf("error");
  	}
  	printf("success");
  
  	return rename_result;
  }
  