Looking for C++ ssh open source client library for windows

I am looking for free c++ ssh-client library for windows . As of now I
have been using plink as ssh command-line utility but in that case i
do not have the freedom of keeping a handle to the connection . I can
see that NetSieben has come-up with a C++ SSH library but that is not
an open-source in complete sense . Please help me if you are aware of
any .