Install using Tinderbox, only 64 bit support maintained although 32 bit should be trivial.
C++ source files are from: https://github.com/eclipse/paho.mqtt.cpp
C compiled libs are from: https://projects.eclipse.org/projects/technology.paho/downloads
Must add a run script at end of build phase with:
install_name_tool -change libpaho-mqtt3a.so.1 @executable_path/libpaho-mqtt3a.so.1 "$TARGET_BUILD_DIR/$PRODUCT_NAME.app/Contents/MacOS/$PRODUCT_NAME"
install_name_tool -change libpaho-mqtt3as.so.1 @executable_path/libpaho-mqtt3as.so.1 "$TARGET_BUILD_DIR/$PRODUCT_NAME.app/Contents/MacOS/$PRODUCT_NAME"
install_name_tool -change libpaho-mqtt3c.so.1 @executable_path/libpaho-mqtt3c.so.1 "$TARGET_BUILD_DIR/$PRODUCT_NAME.app/Contents/MacOS/$PRODUCT_NAME"
install_name_tool -change libpaho-mqtt3cs.so.1 @executable_path/libpaho-mqtt3cs.so.1 "$TARGET_BUILD_DIR/$PRODUCT_NAME.app/Contents/MacOS/$PRODUCT_NAME"
Note that downloaded compiled libs were renamed from *.1.0 to *.1
C libs were compiled from master branch here, with visual studio project taken from develeop branch for x64 support: https://github.com/eclipse/paho.mqtt.c.git
Had to edit $(OpenSSLDir) for 2 of the 4 lib projects to point to this install:
https://slproweb.com/download/Win64OpenSSL-1_0_2h.exe