c_ch01_ex19.c

/*Exercise 1-19. Write a function reverse(s) that reverses the character string s. Use it to write a program that reverses its input a line at a time.*/
#include <stdio.h>
#define MAX     1000
int reverse(char str[], char rev[], int length);
int main()
{
        int length = MAX, max;
        length = max = 0;
        char rev[MAX], str[MAX];
        while ((length = reverse (str, rev, MAX)) > 0)
                printf("%s\n", rev);
        return 0;
}
int reverse(char str[], char rev[], int length) {
        int c, i, j;
        i = j = 0;
        while ((c = getchar()) != EOF && c != '\n' && i < length)
                str[i++] = c;
        while (i > 0)
                rev[j++] = str[--i];
        rev[j] = '\0';
        return j;
}