./xtensa-lx106-elf/xtensa-lx106-elf/sysroot/usr/include/lwip/opt.h
./ESP8266_NONOS_SDK-2.1.0-18-g61248df/third_party/include/lwip/opt.h
./esp-open-lwip/include/lwip/opt.h
I have many questions: Why is it there are three copies? Which one is the toolchain using and why? Should I modify one of those if I want, say, POSIX sockets? Or better yet: where can I find all this documented?
Thanks
Gato