1. CLISH (Command Line Interface SHell)
A modular framework for implementing a CISCO-like CLI on a *NIX system. Arbitary command menus and actions can be defined using XML files. This software handles the user interaction, and forks the appropriate system commands to perform any actions.
2. Libconfig – C/C++ Configuration File Library
Libconfig is a simple library for processing structured configuration files, like this one: test.cfg. This file format is more compact and more readable than XML. And unlike XML, it is type-aware, so it is not necessary to do string parsing in application code.
Libconfig is very compact — a fraction of the size of the expat XML parser library. This makes it well-suited for memory-constrained systems like handheld devices.
3. libevent – an event notification library
The libevent API provides a mechanism to execute a callback function when a specific event occurs on a file descriptor or after a timeout has been reached. Furthermore, libevent also support callbacks due to signals or regular timeouts.
libevent is meant to replace the event loop found in event driven network servers. An application just needs to call event_dispatch() and then add or remove events dynamically without having to change the event loop.
4. libcurl – the multiprotocol file transfer library
libcurl is a free and easy-to-use client-side URL transfer library, supporting DICT, FILE, FTP, FTPS, Gopher, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS, POP3, POP3S, RTMP, RTSP, SCP, SFTP, SMTP, SMTPS, Telnet and TFTP. libcurl supports SSL certificates, HTTP POST, HTTP PUT, FTP uploading, HTTP form based upload, proxies, cookies, user+password authentication (Basic, Digest, NTLM, Negotiate, Kerberos), file transfer resume, http proxy tunneling and more!
libcurl is highly portable, it builds and works identically on numerous platforms, including Solaris, NetBSD, FreeBSD, OpenBSD, Darwin, HPUX, IRIX, AIX, Tru64, Linux, UnixWare, HURD, Windows, Amiga, OS/2, BeOs, Mac OS X, Ultrix, QNX, OpenVMS, RISC OS, Novell NetWare, DOS and more…
libcurl is free, thread-safe, IPv6 compatible, feature rich, well supported, fast, thoroughly documented and is already used by many known, big and successful companies and numerous applications.
5. jsmn – Minimalistic JSON parser in C
jsmn (pronounced like ‘jasmine’) is a minimalistic JSON parser in C. It can be easily integrated into resource-limited or embedded projects.
jsmn is designed to be robust (it should work fine even with erroneous data), fast (it should parse data on the fly), portable (no superfluous dependencies or non-standard C extensions). An of course, simplicity is a key feature – simple code style, simple algorithm, simple integration into other projects.
6. libmraa – Low Level Skeleton Library for Communication on GNU/Linux platforms
The intent is to make it easier for developers and sensor manufacturers to map their sensors & actuators on top of supported hardware and to allow control of low level communication protocol by high level languages & constructs.