Signing a hash using MSVC++

My program which is written in MSVC++ need to sign a h开发者_运维技巧ash. I've found an example from msdn

Can any one please tell how can i use my custom private key to sign the hash. In the example i could not see it accepting a user defined key/text.

Also, please tell me if it is good to store a public key in a text file.

Thank you, John

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Within the Example C Program: Encrypting a File session key derived from a password is used to encrypt data. Of course you have to know the password otherwise you can not be sure who decrypted (or signed in your case).

It's mandatory to make the public part of the key available to everyone otherwise verifying the signature is not possible to someone else. A text file is also ok.