*
* License: BSD-MIT
* Author: Rusty Russell <rusty@rustcorp.com.au>
+ *
+ * Example:
+ *
+ * #include <ccan/crypto/shachain/shachain.h>
+ * #include <ccan/err/err.h>
+ * #include <stdio.h>
+ * #include <stdlib.h>
+ * #include <string.h>
+ *
+ * int main(int argc, char *argv[])
+ * {
+ * size_t i, j, limit = 10;
+ * struct sha256 seed;
+ *
+ * if (argc < 2)
+ * errx(1, "Usage: %s <passphrase> [<num-to-generate>]", argv[0]);
+ * sha256(&seed, argv[1], strlen(argv[1]));
+ * if (argv[2])
+ * limit = atol(argv[2]);
+ *
+ * for (i = 0; i < limit; i++) {
+ * struct sha256 v;
+ * shachain_from_seed(&seed, i, &v);
+ * printf("%zu: ", i);
+ * for (j = 0; j < sizeof(v.u.u8); j++)
+ * printf("%02x", v.u.u8[j]);
+ * printf("\n");
+ * }
+ * return 0;
+ * }
*/
int main(int argc, char *argv[])
{