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+klog
+====
+
+klog is a permanent fork of https://github.com/golang/glog.
+
+## Why was klog created?
+
+The decision to create klog was one that wasn't made lightly, but it was necessary due to some
+drawbacks that are present in [glog](https://github.com/golang/glog). Ultimately, the fork was created due to glog not being under active development; this can be seen in the glog README:
+
+> The code in this repo [...] is not itself under development
+
+This makes us unable to solve many use cases without a fork. The factors that contributed to needing feature development are listed below:
+
+ * `glog` [presents a lot "gotchas"](https://github.com/kubernetes/kubernetes/issues/61006) and introduces challenges in containerized environments, all of which aren't well documented.
+ * `glog` doesn't provide an easy way to test logs, which detracts from the stability of software using it
+ * A long term goal is to implement a logging interface that allows us to add context, change output format, etc.
+
+Historical context is available here:
+
+ * https://github.com/kubernetes/kubernetes/issues/61006
+ * https://github.com/kubernetes/kubernetes/issues/70264
+ * https://groups.google.com/forum/#!msg/kubernetes-sig-architecture/wCWiWf3Juzs/hXRVBH90CgAJ
+ * https://groups.google.com/forum/#!msg/kubernetes-dev/7vnijOMhLS0/1oRiNtigBgAJ
+
+----
+
+How to use klog
+===============
+- Replace imports for `github.com/golang/glog` with `k8s.io/klog`
+- Use `klog.InitFlags(nil)` explicitly for initializing global flags as we no longer use `init()` method to register the flags
+- You can now use `log_file` instead of `log_dir` for logging to a single file (See `examples/log_file/usage_log_file.go`)
+- If you want to redirect everything logged using klog somewhere else (say syslog!), you can use `klog.SetOutput()` method and supply a `io.Writer`. (See `examples/set_output/usage_set_output.go`)
+- For more logging conventions (See [Logging Conventions](https://github.com/kubernetes/community/blob/master/contributors/devel/sig-instrumentation/logging.md))
+
+**NOTE**: please use the newer go versions that support semantic import versioning in modules, ideally go 1.11.4 or greater.
+
+### Coexisting with glog
+This package can be used side by side with glog. [This example](examples/coexist_glog/coexist_glog.go) shows how to initialize and synchronize flags from the global `flag.CommandLine` FlagSet. In addition, the example makes use of stderr as combined output by setting `alsologtostderr` (or `logtostderr`) to `true`.
+
+## Community, discussion, contribution, and support
+
+Learn how to engage with the Kubernetes community on the [community page](http://kubernetes.io/community/).
+
+You can reach the maintainers of this project at:
+
+- [Slack](https://kubernetes.slack.com/messages/klog)
+- [Mailing List](https://groups.google.com/forum/#!forum/kubernetes-sig-architecture)
+
+### Code of conduct
+
+Participation in the Kubernetes community is governed by the [Kubernetes Code of Conduct](code-of-conduct.md).
+
+----
+
+glog
+====
+
+Leveled execution logs for Go.
+
+This is an efficient pure Go implementation of leveled logs in the
+manner of the open source C++ package
+ https://github.com/google/glog
+
+By binding methods to booleans it is possible to use the log package
+without paying the expense of evaluating the arguments to the log.
+Through the -vmodule flag, the package also provides fine-grained
+control over logging at the file level.
+
+The comment from glog.go introduces the ideas:
+
+ Package glog implements logging analogous to the Google-internal
+ C++ INFO/ERROR/V setup. It provides functions Info, Warning,
+ Error, Fatal, plus formatting variants such as Infof. It
+ also provides V-style logging controlled by the -v and
+ -vmodule=file=2 flags.
+
+ Basic examples:
+
+ glog.Info("Prepare to repel boarders")
+
+ glog.Fatalf("Initialization failed: %s", err)
+
+ See the documentation for the V function for an explanation
+ of these examples:
+
+ if glog.V(2) {
+ glog.Info("Starting transaction...")
+ }
+
+ glog.V(2).Infoln("Processed", nItems, "elements")
+
+
+The repository contains an open source version of the log package
+used inside Google. The master copy of the source lives inside
+Google, not here. The code in this repo is for export only and is not itself
+under development. Feature requests will be ignored.
+
+Send bug reports to golang-nuts@googlegroups.com.