Как вывести строки в обратном порядке из одного файла в другой?

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

#define LINES 10	// Number of lines
#define CHARS 10	// Number of characters at line

char randomChar()
{
#if 0
	float f = rand();
	f /= RAND_MAX;
	return (char) (10 * f + '0');
#else
	static char n = 'A';
	if (++n > 'Z' && n < 'a')
		n = 'a';
	if (n > 'z')
		n = 'A';
	return n;
#endif
}

void getputChar(FILE* infile, FILE* outfile)
{
	char ch;

	ch = fgetc(infile);
	if (ferror(infile))
		perror("Error reading file f1.txt");
	fputc(ch, outfile);
	if (ferror(outfile))
		perror("Error writing file f2.txt");
}

int reverseOrder(FILE* infile, int pos, FILE* outfile)
{
	int npos = pos;
	char ch;
	int count;
	int n;

	while (1) {
		ch = fgetc(infile);
		if (ferror(infile))
			perror("Error reading file f1.txt");
		if (ch == '\n') {
			count = reverseOrder(infile, npos+1, outfile) + 1;
			fseek(infile, pos, SEEK_SET);
			if (ferror(infile))
				perror("Error seeking file f1.txt");
			for (n = 0; n < count; ++n)
				getputChar(infile, outfile);
			fputc('\n', outfile);
			if (ferror(outfile))
				perror("Error writing file f2.txt");
			return count;
		}
		else if (ch == EOF) {
			if (npos - pos == 0)
				return 0;
			else {
				fseek(infile, pos, SEEK_SET);
				if (ferror(infile))
					perror("Error seeking file f1.txt");
				getputChar(infile, outfile);
				fputc('\n', outfile);
				if (ferror(outfile))
					perror("Error writing file f2.txt");
				return 1;
			}
		}
		else {
			npos++;
		}
	}
}

int main()
{
	FILE* file_ptr;
	FILE* file_ptr1;
	int n, nn;

	// Creating file f1.txt
	file_ptr = fopen("f1.txt", "w");
	if (file_ptr == NULL) {
		perror("Error creating file f1.txt");
	}

	srand(time(0));
	for (n = 0; n < LINES; ++n) {
		for(nn = 0; nn < CHARS; ++nn) {
			fputc(randomChar(), file_ptr);
			if (ferror(file_ptr)) {
				perror("Error writing file f1.txt");
			}
		}
		fputc('\n', file_ptr);
	}
	fclose(file_ptr);

	// Reverse order of lines
	file_ptr = fopen("f1.txt", "r");
	if (file_ptr == NULL) {
		perror("Error opening file f1.txt");
	}

	file_ptr1 = fopen("f2.txt", "w");
	if (file_ptr1 == NULL) {
		perror("Error creating file f2.txt");
	}

	reverseOrder(file_ptr, 0, file_ptr1);

	fclose(file_ptr1);
	fclose(file_ptr);
	printf("OK\n");

	return EXIT_SUCCESS;
}