eUtils/c_src/.enq/rebar.config

{port_specs, [
    {"../../priv/enq_nif.so", ["*.c"]}
]}.

% {port_env, [
%     {"LDFLAGS", "$ERL_LDFLAGS -lrt"},
%     {"CFLAGS", "$CFLAGS --std=gnu99 -Wall -O3"}
% ]}.