fold.c

/* fold.c nバイトずつ折り返す */
#include <stdio.h>
#include <stdlib.h>

int main(int argc, char const* argv[])
{
        if(argc != 2)
                exit(1);

        int i = 0;
        long n = strtol(argv[1],NULL,10);

        if(n <= 0 || n > 1024)
                exit(1);

        while(1){
                for(i=0;i<n;i++){
                        int a = getchar();
                        if(a == EOF)
                                exit(0);

                        putchar(a);
                }
                putchar('\n');
        }
        exit(0);
}