n.</p>

<p>BN_is_prime_ex(), BN_is_prime_fasttest_ex(), BN_is_prime() and BN_is_prime_fasttest() are deprecated.</p>

<p>BN_is_prime_fasttest() and BN_is_prime() behave just like BN_is_prime_fasttest_ex() and BN_is_prime_ex() respectively, but with the old style call back.</p>

<p><b>ctx</b> is a preallocated <b>BN_CTX</b> (to save the overhead of allocating and freeing the structure in a loop), or <b>NULL</b>.</p>

<p>If the trial division is done, and no divisors are found and <b>cb</b> is not <b>NULL</b>