Nybörjare till C och jag har lite frågor om getopt

#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int
main (int argc, char **argv)
{
  int hflag = 0;
  int pflag = 0;
  char *cvalue = NULL;
  int index;
  int c;

  opterr = 0;

  // Loopa igenom alla argument och kolla vilka som är satta
  while ((c = getopt (argc, argv, "abc:")) != -1)
    switch (c)
      {
      case 'h':
        hflag = 1;
        break;
      case 'p':
        pflag = 1;
        break;
      case 'c':
        cvalue = optarg;
        break;
      case '?':
        if (optopt == 'c')
          fprintf (stderr, "Option -%c requires an argument.\n", optopt);
        else if (isprint (optopt))
          fprintf (stderr, "Unknown option `-%c'.\n", optopt);
        else
          fprintf (stderr,
                   "Unknown option character `\\x%x'.\n",
                   optopt);
        return 1;
      default:
        abort ();
      }

  if(hflag) { // Om h-flaggan är satt
      print_help_message();
      exit(EXIT_SUCCESS);
  }  

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include "utils.h"

#define USAGE "Usage: countln [filename] [-p filename]\n"
int main (int argc, char *argv[]) {


size_t lines;
int opt;
int returnval;

while ((opt = getopt(argc, argv, "p:h")) != -1) {
        switch (opt) {
        
	    case 'p':

            returnval = COUNT_LINES_IN_FILE_POSIX(optarg, &lines);
            if (returnval == 1) {
                return EXIT_FAILURE;
            }
            fprintf(stdout, "Number of lines: %ld\n", lines);
	    break;

        case 'h':

            fprintf(stdout, "%s", USAGE);
            return EXIT_SUCCESS;

        break;

        default: 
            fprintf(stderr, "%s", USAGE);
            return EXIT_FAILURE;
        }
}
    
    if (argc == 1) {
        fprintf(stderr, "%s: Please provide a file.\n%s", argv[0], USAGE);
	    return EXIT_FAILURE;
    } 
    
    if (argc == 2) {
        returnval = COUNT_LINES_IN_FILE(argv[1], &lines);
        if (returnval == 1) {
            return EXIT_FAILURE;
        }
        fprintf(stdout, "Number of lines: %ld\n", lines);
    }

return EXIT_SUCCESS;

}