void BLOT(ctx)
EVP_ENCODE_CTX *ctx;
void BLOT_encode(ctx,out,outl,in,inl)
EVP_ENCODE_CTX *ctx;
unsigned char *out, *in;
int *outl, inl;
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BLOT_encode is too, but for purposes of illustration we assume that it copies inl bytes of the input string in into a previously-initialized ctx; if any data was already stored in the ctx, it is base64-encoded first and the results written to out. The number of bytes written to out is placed in outl.
Note that the first time this function is called, the input string is copied into the ctx but since there is no input data already in ctx, no data is base64-encoded. In effect, output is always one function call behind the input.
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