i2d_X509_bio
if (!i2d_X509_bio(bp, x))
i = i2d_X509_bio(out, x509ss);
i = (int) i2d_X509_bio(out, peer);
i = i2d_X509_bio(out, x);
int i2d_X509_bio(BIO *bp,X509 *x509);