#include #include DEFINE_string(message, "Hello World!", "The message to print"); static bool ValidateMessage(const char* flagname, const std::string &message) { return !message.empty(); } DEFINE_validator(message, ValidateMessage); int main(int argc, char **argv) { gflags::SetUsageMessage("Test CMake configuration of gflags library (gflags-config.cmake)"); gflags::SetVersionString("0.1"); gflags::ParseCommandLineFlags(&argc, &argv, true); std::cout << FLAGS_message << std::endl; gflags::ShutDownCommandLineFlags(); return 0; }