libnetfilter_cttimeout is an interface to Netfilter Connection Tracking timeouts. It provides a userspace library which provides a programming interface to the fine-grained connection tracking timeout infrastructure. With this library, you can create, update, and delete timeout policies which can be attached to traffic flows.
libpersist is a small library of C++ base classes and templates providing the capability to store and load objects in their entirety across executions. It also provides for object relocation between threads in a NUMA (non-uniform memory access) parallel processing environment. Objects are stored to disk as POD. They are reconstructed when reloaded into memory. Relocation is a special case of persistence, requiring reconstruction after the POD has been moved in memory. After all objects have been relocated, all references to the objects are swizzled (their IDs are resolved to their addresses), so that they can be dereferenced efficiently.
libphidgets is a user-space access library for the Phidget devices. It provides a generic and flexible way to access and interact with the Phidgets, and comes with all the advantages of a user-space library. It is based on libhid (which is based on libusb), thus it requires no HID support in the kernel. Furthermore, it aims to support all operating system supported by libusb/libhid: Linux, BSD, OS X, and Windows.
Libpsl is a C library which provides functions to check domains against the Mozilla Public Suffix List. It is useful for cookie domain verification, certificate domain verification, highlighting parts of a domain name, and more. Every Web client handling cookies (e.g. browsers) should use the PSL data to secure privacy.
libqt4jon is a JSON serializer and deserializer that works with the Qt QVariant object. It can serialize primitives like integer, double, QString, lists, maps, and QObject * recursively. It serializes only properties declared with the QObject * Q_PROPERTY macro. It based on the json-c parser.