glog: use os.Stderr directly for writing to stderr (#62)

This was raised in

Before the 1.1.0 release it was possible to set os.Stderr to a different *os.File (like an os.Pipe) to capture output that is written to stderr. Restore that behavior.
1 file changed
tree: 22ea471ccced2d60d92390de04654ca492a16013
  1. internal/
  2. glog.go
  3. glog_bench_test.go
  4. glog_file.go
  5. glog_file_linux.go
  6. glog_file_other.go
  7. glog_file_posix.go
  8. glog_flags.go
  9. glog_test.go
  10. glog_vmodule_test.go
  11. go.mod



Leveled execution logs for Go.

This is an efficient pure Go implementation of leveled logs in the manner of the open source C++ package 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 the functions Info, Warning, Error, Fatal, plus formatting variants such as Infof. It also provides V-style loggingcontrolled 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