// 2>/dev/null; X=${0%.c}; [ "$X" -nt "$0" ] || cc -o "$X" -Wall -x c "$0" && exec "$X" "$@"; exit

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

#define MAX_LINE 4096

int main(int argc, char *argv[])
{
	int n, i;
	char **files;
	FILE **fps;
	char *line = NULL;
	size_t len = 0;
	ssize_t linelen;

	if (argc < 2) {
		fprintf(stderr, "usage: %s outfile ...\n", argv[0]);
		exit(1);
	}
	n = argc - 1;
	files = argv + 1;
	fps = malloc(n*sizeof(FILE*));
	for (i=0; i<n; ++i) {
		fps[i] = fopen(files[i], "w");
		if (!fps[i]) {
			perror("failed fopen");
			exit(1);
		}
	}

	i = 0;
	while ((linelen = getline(&line, &len, stdin)) != -1) {
		if (fwrite(line, 1, linelen, fps[i]) != linelen) {
			fprintf(stderr, "failed fwrite\n");
			exit(1);
		}
		++i;
		if (i == n)
			i = 0;
	}

	for (i=0; i<n; ++i) {
		if (fclose(fps[i]) != 0) {
			perror("failed fclose");
			exit(1);
		}
	}

	return 0;
}