Chapter 7 - Input and Output 8

Write a program to print a set of files, starting each new one on a new page, with a title and a running page count for each file.

Solution by Steven Huang .

/* K&R Exercise 7-8 */
/* Steven Huang */

/*
   Limitation:  This program doesn't wrap long lines.
*/
 
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>

#define LINES_PER_PAGE 10
#define TRUE           1
#define FALSE          0

void print_file(char *file_name)
{
  FILE *f;
  int page_number = 1;
  int line_count;   
  int c;       
  int new_page = TRUE;
 
  assert(file_name != NULL);

  if ((f = fopen(file_name, "r")) != NULL) {
    while ((c = fgetc(f)) != EOF) {
      if (new_page) { 
        /* print out the header */
        printf("[%s] page %d starts\n", file_name, page_number);
        new_page = FALSE;
        line_count = 1;
      }               
      putchar(c);
      if (c == '\n' && ++line_count > LINES_PER_PAGE) {
        /* print out the footer */
        printf("[%s] page %d ends\n", file_name, page_number);
        /* skip another line so we can see it on screen */
        putchar('\n');
        new_page = TRUE;
        page_number++;
      }             
    }
    if (!new_page) {
      /* file ended in the middle of a page, so we still need to
         print a footer */
      printf("[%s] page %d ends\n", file_name, page_number);
    }
    /* skip another line so we can see it on screen */
    putchar('\n');   
    fclose(f);
  }
}

int main(int argc, char *argv[])
{
  int i;

  if (argc < 2) {
    fputs("no files specified\n", stderr);
    return EXIT_FAILURE;
  }
  for (i = 1; i < argc; i++) {
    print_file(argv[i]);
  }
  return EXIT_SUCCESS;
}