HSH_MAGIC_SIZE
if (!memcmp(header.hsh_magic, hsh_magic_val, HSH_MAGIC_SIZE)) {
memcpy(header.hsh_magic, hsh_magic_val, HSH_MAGIC_SIZE);
static const char hsh_magic_val[HSH_MAGIC_SIZE] = "//:\0\0://";
char hsh_magic[HSH_MAGIC_SIZE];