LGPLv2+ and LGPLv2+ with exceptions and GPLv2+ and GPLv2+ with exceptions and BSD and Inner-Net-2.0 and ISC and Public Domain and GFDL-1.3-only
libverto exists to solve an important problem: many applications and libraries are unable to write asynchronous code because they are unable to pick an event loop. This is particularly true of libraries who want to be useful to many applications who use loops that do not integrate with one another or which use home-grown loops. libverto provides a loop-neutral async api which allows the library to expose asynchronous interfaces and offload the choice of the main loop to the application.
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A high-performance event loop/event model with lots of features
Libev is modeled (very loosely) after libevent and the Event Perl module, but is faster, scales better and is more correct, and also more featureful. And also smaller.
The GNU C Library project provides the core libraries for the GNU system and GNU/Linux systems, as well as many other systems that use Linux as the kernel. These libraries provide critical APIs including ISO C11, POSIX.1-2008, BSD, OS-specific APIs and more. These APIs include such foundational facilities as open, read, write, malloc, printf, getaddrinfo, dlopen, pthread_create, crypt, login, exit and more.
The core library that forms the basis for projects such as GTK+ and GNOME
GLib is a bundle of three (formerly five) low-level system libraries written in C and developed mainly by GNOME. GLib's code was separated from GTK, so it can be used by software other than GNOME and has been developed in parallel ever since.
Libevent additionally provides a sophisticated framework for buffered network IO, with support for sockets, filters, rate-limiting, SSL, zero-copy file transmission, and IOCP. Libevent includes support for several useful protocols, including DNS, HTTP, and a minimal RPC framewor.