Thread: Logic approach

I have fixed the -s option to eliminate excess blank lines but still am having some difficulty with parsing multiple command line options eg -ns. Is it possible to do this using this approach that i am trying?

If i attempt to pass ./prog -ns file.txt in the command line it returns

Case n!
File -ns couldn't be opened!
Segmentation fault

Rather than listing lines and eliminating excess blank lines.
When -n file.txt is passed it no longer prints newlines due to my logic problem.

Code:

   void concatenate_files(char option){
    for(index = optind; index < argc; index++){
      fp = fopen(argv[index], "r");
      if(fp == NULL){
        fprintf(stdout,"File %s couldn't be opened!\n", argv[index]);
      }else{
        printf("File opened!\n");
      }
        printf("%c\n", option);
        int c;
        int aflag = 1;
        int bflag = 1;
        while((c = fgetc(fp)) != EOF){
          if(aflag != 0 && option == 'n'){
            printf("%d  ", lineCount);
            lineCount++;
            aflag = 0;
          }
          if(c == '\n' && bflag != 0 && option == 's'){
            printf("%c", c);
            bflag = 0;
          }
          if(c != '\n'){
            printf("%c", c);
            bflag = 1;
          }
          if(c == '\n'){
            aflag = 1;
          }
        }
      fclose(fp);
    }
  }

Code:

  while((optchar = getopt (argc, argv, "nsvt")) != -1){
    switch(optchar){
      case 'n':
            printf("Case n!\n");
            concatenate_files('n');
        break;
      case 's':
             printf("Case s!\n");
             concatenate_files('s');
        break;
      case 'v':
        break;
      case 't':
        break;
      }
    }