Some quick background, I am trying to get mosquitto to work with both websocket support and mysql back auth-plugin. I am using version 1.5.5 of the mosquitto broker as this works with the auth-plugin and supports websockets.

I build the program first using and older version of the libwebsocket, before realising that I needed to use version 2.4.2.

I am running Ubuntu 18.04 LTS

ldd /usr/local/sbin/mosquitto

linux-vdso.so.1 (0x00007ffcf7ff9000)
libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f3f2eb9a000)
libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f3f2e7fc000)
librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007f3f2e5f4000)
libssl.so.1.1 => /usr/local/lib/libssl.so.1.1 (0x00007f3f2e361000)
libcrypto.so.1.1 => /usr/local/lib/libcrypto.so.1.1 (0x00007f3f2de74000)
libuuid.so.1 => /lib/x86_64-linux-gnu/libuuid.so.1 (0x00007f3f2dc6d000)
**libwebsockets.so.9 => /usr/lib/libwebsockets.so.9 (0x00007f3f2da47000)**
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f3f2d656000)
/lib64/ld-linux-x86-64.so.2 (0x00007f3f2efcd000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f3f2d437000)
libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f3f2d21a000)

How do I update this line libwebsockets.so.9 => /usr/lib/libwebsockets.so.9 (0x00007f3f2da47000).

I have rebuilt lws using 2.4.2 which gives the libwebsockets.so.12 object file but I don't know to link it to mosquitto?

Commands used to rebuild lws-2.4.2

cd /home/ubuntu/mqtt/websockets/
sudo cp /home/ubuntu/mosquitto_installer/install/libwebsockets-2.4.2.tar.gz .
sudo tar zxvf libwebsockets-2.4.2.tar.gz
sudo chmod 777 libwebsockets-2.4.2
cd libwebsockets-2.4.2/
mkdir build
cd build
sudo cmake ..
sudo make
sudo make install
sudo ldconfig

If this is off-topic just let me and I will post elsewhere.