get Tradfri HomeKit code

You will need to install COAP client... I forgot from where I did instal it, sorry :(  (it's long time ago)

1. Create identity:
 coap-client -m post -u "Client_identity" -k "YOUR_SECURITY_CODE" -e '{"9090":"IDENTITY"}' "coaps://YOUR_GW_IP:5684/15011/9063"

2. You will get pre-sared key in response
 {"9091":"YOUR_PRESHARED_KEY","9029":"1.2.0042"}

3. Ask the gateway for info (/15011/15012 command)
 coap-client -m get -u "IDENTITY" -k "YOUR_PRESHARED_KEY" "coaps://YOUR_GW_IP:5684/15011/15012"
 
4. You will get long response... look for number in format XXX-XX-XXX - this is your HomeKit Code!
 
NOTES:
 YOUR_SECURITY_CODE - it's printet on the bottom of the gateway
 IDENTITY - seems like it is an name/id of the identity... I just used the word "IDENTITY" and it worked.
 YOUT_GW_IP - well, IP address :D
 YOUR_PRESHARED_KEY - random characters "password" for your identity... Just keep it safe :)

building coap-client

git clone --depth 1 --recursive -b dtls https://github.com/home-assistant/libcoap.git
cd libcoap
./autogen.sh
./configure --disable-documentation --disable-shared --without-debug CFLAGS="-D COAP_DEBUG_FD=stderr"
make
sudo make install

Problem with your script on my Mac :/ Idea ?