file.c

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

int *char2ascii(int arr[8], char c);
void convertToBinary(int arr[8], char c);
void printBinart(int arr[8]);

int main(int argc, char **argv) {
  char c;
  int arr[8];

  int flag = argc > 1 ? strcmp(argv[1], "-l") : 1;

  while ((c = getchar() ) != EOF) {
    if (flag) {
      if (c == 10)
        printf("\n");
      else {
        convertToBinary(arr, c);
        printBinart(arr);

      }
    }
  }
  return 0;
}


void convertToBinary(int arr[8], char c) {
  int i;
  for (i = 0; i < 8; ++i) {
    if (c % 2 == 0)
      arr[i] = 0;
    else
      arr[i] = 1;
    c = c / 2;
  }
}

void printBinart(int arr[8]) {
  int j;
  for (j = 0; j < 8; ++j) {
    printf("%d", arr[j]);
  }

}