+/*
+ * Copyright 2004-present Facebook, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <folly/experimental/logging/Init.h>
+#include <folly/experimental/logging/xlog.h>
+#include <folly/init/Init.h>
+
+#include <folly/experimental/logging/example/lib.h>
+
+DEFINE_string(logging, "", "Logging category configuration string");
+
+using namespace example;
+using folly::LogLevel;
+
+// Invoking code that uses XLOG() statements before main is safe,
+// but will not log anywhere, since no handlers are configured yet.
+static ExampleObject staticInitialized("static");
+
+int main(int argc, char* argv[]) {
+ // Using log macros before configuring any log levels or log handlers is
+ // safe, but the messages will always be ignore since no handlers are defined.
+ XLOG(INFO, "no handlers configured yet, so this will go nowhere");
+ printf("main starting\n");
+ fflush(stdout);
+
+ // Call folly::init() and then initialize log levels and handlers
+ folly::init(&argc, &argv);
+ initLoggingGlogStyle(FLAGS_logging, LogLevel::INFO);
+
+ // All XLOG() statements in this file will log to the category
+ // folly.experimental.logging.example.main
+ XLOG(INFO, "now log messages will be sent to stderr");
+
+ XLOG(DBG1, "log arguments are concatenated: ", 12345, ", ", 92.0);
+ XLOGF(DBG1, "XLOGF supports {}-style formatting: {:.3f}", "python", 1.0 / 3);
+ XLOG(DBG2) << "streaming syntax is also supported: " << 1234;
+ XLOG(DBG2, "you can even", " mix function-style") << " and streaming "
+ << "syntax";
+
+ ExampleObject("foo");
+ XLOG(INFO, "main returning");
+ return 0;
+}