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API
From OpenSSLWiki
Placeholder for an overview of the OpenSSL API
Some languages comes with openssl wrapper to provide openssl acces within native. Whole Openssl library API is in 'C' ie you need to compile with C headers and link with libraries.
C API
Python API
M2Crypto
http://chandlerproject.org/Projects/MeTooCrypto
PyOpenssl
https://launchpad.net/pyopenssl