DataReel is a free, cross-platform database and communications toolkit. It can be used to rapidly develop and deploy multi-threaded database and communications applications. The DataReel toolkit is composed of a modular C++ library designed to build cross-platform infrastructures for end-user applications, embedded systems, and reusable libraries. DataReel's unique modular design simplifies adaptation, allowing you to determine the level of complexity. DataReel makes Internet connectivity and database programming easy.
IP*Works! is a comprehensive suite of more than 40 native Linux class libraries for Internet development. It is a robust framework of enterprise-class tools, enabling rapid integration of any major Internet protocol or technology, including FTP, HTTP, SMTP, POP, IMAP, SNMP, LDAP, DNS, RSS, SMPP(SMS), XMPP (Jabber), SOAP, and WebDav. It includes source code for compilation on various Unix platforms, a framework for Objective-C (Cocoa) Mac OS X development, and native PHP extensions.
KindFTP is meant to be a complete implementation of the FTP protocol, as specified in RFC959. It provides a component that directly exposes the low-level protocol, and it supports the core protocol that is available on most Open Source FTP servers. It has untested support for ACCT, SMNT, REIN, TYPE, STRU, MODE, ALLO, and SITE command. It uses iContract to provide a full formal specification of all software, jUnit for all unit testing, and Ant as a build tool.