IV handling in symmetric modes in libgcrypt

[Damian Vizar]

Hi,

I have a fairly simple question: for the symmetric blockcipher modes of 
operation (I am mostly interested in AEAD modes), does the IV have to be 
re-set manually for every encryption, or is there some mechanism that 
updates the IV automatically? (E.g. by counter-like incrementation).

I tried to figure it out on my own, but I am not familiar with the code 
of libgcrypt.

Thanks,
Damian