Russel Coker thinks you're too sloppy with const among other things. See http://bugs.debian.org/524133. Here is a patch. Naturally, you have to enable warnings to see them. :-)
Additionally the szBuffer argument to DKIMSignProcess() and DKIMVerifyProcess() should be const. That would allow users to pass const data into this functions without casting.
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Fix most compiler warnings
Additionally the szBuffer argument to DKIMSignProcess() and DKIMVerifyProcess() should be const. That would allow users to pass const data into this functions without casting.