Possible to calculate MD5 (or other) hash with buffered reads?

Question

I need to calculate checksums of quite large files (gigabytes). This can be accomplished using the following method:

    private byte[] calcHash(string file         


        

Answer 1

Hash algorithms are expected to handle this situation and are typically implemented with 3 functions:

hash_init() - Called to allocate resources and begin the hash.
hash_update() - Called with new data as it arrives.
hash_final() - Complete the calculation and free resources.

Look at http://www.openssl.org/docs/crypto/md5.html or http://www.openssl.org/docs/crypto/sha.html for good, standard examples in C; I'm sure there are similar libraries for your platform.