Hello,
we successfully ported the mosquitto *library* to Genode (we used version 15.05 and 16.08 for testing), which may be interesting for some on the mailing list - it is a library, implementing the MQTT protocol.
https://github.com/argos-research/genode/pull/12
Every option is enabled apart from 'WITH_SRV' which would enable SRV lookup support. We didn't test the SSL support, but it is linked and compiled into the library.
Additionally a simple publisher application is implemented (mpct), which publishes to a given server a hello world message with an increasing iterator and makes use of the callback functionality.
One point which took a huge amount of time to find, was that 'lwip_tcpip_init()' function leads to freezes for us (https://github.com/argos-research/genode/pull/12/files#diff-48dce339109d6267...). On real hardware (pandaboard / raspberry pi) it freezes before even receiving an ip address and on the pbxa9 qemu instance it froze after publishing a few messages, leading to the error message 'Assertion "tcp_write: pbufs on queue => at least one queue non-empty"'. To work around this, by simply removing it, everything seems to work and we are not exactly sure why, maybe someone can explain it to us?
Regards, Alexander