Although I have not read the code, I find that PDFLib
has an extremely good and easy-to-use API to an underlying C library. The rather amazing thing is that they support something like 7 languages over this library. It is proprietary, but still pretty cool.
We are the carpenters and bricklayers of the Information Age.
Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.
Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.