How to encrypt a password

Hi

I'm new to c. What I'd like to do is md5 hash a password, but I'm
having problems with the basics. My main problem is I'm wobbly on
knowing where to start from. I assumed I'd use md5.h in my program, but
how do I know what functons to use or exist to be used?

Could somone help me with this?

Thanks in advance
Dan

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