CRYPTO_memcmp - Constant time memory comparison

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       Licensed under the Apache License 2.0 (the "License").  You may not use this file except in compliance
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3.5.0                                              2025-06-04                                CRYPTO_MEMCMP(3SSL)

       The CRYPTO_memcmp function compares the len bytes pointed to by a and b for equality.  It takes an amount
       of time dependent on len, but independent of the contents of the memory regions pointed to by a and b.

       CRYPTO_memcmp - Constant time memory comparison

       Unlike memcmp(2), this function cannot be used to order the two memory regions as the return value when
       they differ is undefined, other than being nonzero.

CRYPTO_memcmp() returns 0 if the memory regions are equal and nonzero otherwise.

        #include <openssl/crypto.h>

        int CRYPTO_memcmp(const void *a, const void *b, size_t len);