text: #include <stdio.h>
  #include <stdlib.h>
  #include <errno.h>
  
  /**
   * Main.
   */
  int main () {
      
      FILE *file;
  
      file = fopen("./file.txt","rt");
      
      if(file == NULL) {
          printf("File cannot be opened");
      }
  
      FILE *file2 = fopen("./file.txt","rt");
      
      if(file2 == NULL) { 
          switch(errno) {
              case ENOENT: printf("The file doesn't exist\n"); 
                   break;
              case EMFILE: printf("You've opened too many files\n"); 
                   break;
              default:     printf("The error number is %d\n",errno);
          }
      }
      
      return 0;
  }