Non GPL C/C++ XMPP client library for embedded Linux
libstrophe - dual-licensed under Mit/GPLv3. However, I'm not sure if it will compile on ARM, although it should be fairly portable.
so I'm not sure why a library requires it.
Because Qt provides XML parser and signal/slot framework. XMPP requires XML parser, and signal/slot framework makes your life easier. If you try implementing entire XMPP with all extensions in OOP fashion, you'll need something similar to Qt. If you simply need to send a command or two, then bare bones solution will do.
libstrophe is bare bones. You won't get dozens of wrappers representing different xmpp concepts (and legion of extensions), but you'll be able to send commands you need/want. You'll have to read XMPP specifications, of course.
Advice: when it comes to C++, there aren't many good xmpp libraries available.
I think it happens for following reasons (personal opinion):
- Too many protocol extensions
- It is easy to get distracted while making xmpp libraries. Xmpp contains fairly large number of possible errors, and OOP-minded programmist will be extremely tempted to make a class for everything, which doesn't work well in this scenario and requires something like Qt 4 to make it work properly.
- XMPP requires XML parser.
As a result, it might make sense to try python - IF your embedded platform can handle it. For python, there's xmpppy. Although I strongly dislike python, I think it'll be easier to work with XMPP in python using xmpppy than in C++ using libstrophe. This is because xmpp requires plenty of key-value pair lists, and python represents such constructs in more "natural" way, using dictionaries.