This is the developer manual for libnfc. libnfc is an open source library that allows you to communicate with NFC devices. For more info, see the libnfc homepage.
If you are looking for libnfc's public API, you should start with the Modules page which links to the different categories of libnfc's functionality. Some commented examples that present how to use libnfc can be found here: Examples
Others example programs can be found in the libnfc source distribution under the "examples" subdirectory examples.
You can also find utils in the libnfc source distribution under the "utils" subdirectory utils.
libnfc functions typically return 0 or more on success or a negative error code on failure. These negative error codes relate to LIBNFC_ERROR constants which are listed on the Error reporting documentation page.
If you are upgrading from a previous libnfc version, please take care about changes, specially API changes. All important changes should be listed in ChangeLog.