The PHP function hash_pbkdf2 does not generate it’s own salt nor does it append a salt to the output.
string hash_pbkdf2 ( string $algo , string $password , string $salt , int $iterations [, int $length = 0 [, bool $raw_output = false ]] )
The caller controls the output length, salt, iteration count and there are 45 hash algorythms to choose from.
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