root@secret~/multiplayerpiano-server-master# make
mkdir -p build
g++ -std=c++11 -Wall -Wextra -Wno-unknown-pragmas -Wno-unused-parameter -MMD -MP -I ./src/ -I ./lib/uWebSockets/src/ -I ./lib/json/include/ -O2 -c -o build/server.o src/server.cpp
In file included from ./lib/uWebSockets/src/WebSocketProtocol.h:5:0,
from ./lib/uWebSockets/src/WebSocket.h:4,
from ./lib/uWebSockets/src/Group.h:4,
from ./lib/uWebSockets/src/Hub.h:4,
from ./lib/uWebSockets/src/uWS.h:4,
from src/server.hpp:1,
from src/server.cpp:1:
./lib/uWebSockets/src/Networking.h:7:30: fatal error: openssl/opensslv.h: No such file or directory
#include <openssl/opensslv.h>
^
compilation terminated.
Makefile:48: recipe for target 'build/server.o' failed
make: *** [build/server.o] Error 1