Queries the entropy gathering daemon EGD on socket path given by
filename.
Fetches length number of bytes and uses ::add to seed the OpenSSL built-in PRNG.
static VALUE
ossl_rand_egd_bytes(VALUE self, VALUE filename, VALUE len)
{
int n = NUM2INT(len);
SafeStringValue(filename);
if (!RAND_egd_bytes(RSTRING_PTR(filename), n)) {
ossl_raise(eRandomError, NULL);
}
return Qtrue;
}