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

#define TRUE 0
#define FALSE 1
#define LINELENGTH 80

char *line;
char *word;

/* reads a line; returns number of characters read */
int getline (FILE *fp) {

  int i = 0;
  char c;

  c = fgetc(fp);
  while ((c != EOF) && (c != '\n')) {
    if (i == LINELENGTH) {
      fprintf (stderr, "Line too long, aborting!\n");
      exit (1);
    }
    line[i] = c;
    i++;
    c = fgetc(fp);
  }
  return i;
}
	
/* check line for occurrences of character a */
int checkOccurrence (char *line) {
  
  int result = FALSE;

  /* inspect each character in turn */
  while (line) {
    if (line == 'a') {
      result = TRUE;
    }
    line++;
  }
  return result;
}
	
      
      
int main (int argc, char **argv) {

  
  FILE *fp;
  int count;
  int charInLine;

  /* check for correct number of arguments */
  if (argc != 2) {
    fprintf (stderr, "%s: Exactly one argument required\n", argv[0]);
    exit (1);
  }

  argv++;

  /* open file for reading */
  fp = fopen (*argv, "r");
  if (!fp) {
    fprintf (stderr, "%s: Couldn't open file %s\n", argv[0], argv[1]);
    exit (1);
  }

  /* reading lines from file */
  charInLine = getline (fp);
  while (charInLine != 0) {
    /* check for lines */
    if (checkOccurrence (line)) {
      count ++;
    }
    printf ("Having read line %s\n", line);

    charInLine = getline (fp);
  }
  
  printf ("The number of lines containing a is %d\n", count);
  fclose (fp);
  return 0;
}