Type mismatch. Expecting a LexBuffer but given a LexBuffer The type 'char' does not match the type 'byte' This is the error message that I am getting while using fslex. I have tried manually checking every single occurrence of lexbuf and its type. It's LexBuffer everywhere. But still the compiler is giving me the above error. Can you please tell me why this error occurs and how to go about resolving it. Thanks, chandrasekhar