Metainfo cheksum calculation

Hello

Anybody who can help to explain how to calculate the metainfo checksum on the metainfo.txt file ?

I understand it needs to be signed afterwards, I would like to know how to calculate the metainfo checksum. It is SHA1, but from where to where to select to get the correct result.

Thanks and regards

Depends on platform.

All lines of the meatinfo2.txt w/o the checksum its self and the signature.