Developers should take steps to prevent sensitive information such as passwords, cryptographic keys, and other secrets from being inadvertently written out to disk or other auxiliary storagevisible to other applications. This includes attempting to prevent such data from being written to disk.
Two common mechanisms by which data can inadvertently be written to disk are swapping and core dumps.
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Additionally processes with elevated privileges can disable paging by "locking" memory in place using either mlock() (UnixPOSIX) or VirtualLock() (Windows). This ensures that memory is never copied to the hard drive where it may be retained indefinitely in non-volatile storage.
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