Clone this repo:
  1. 03ad3c2 glog: use os.Stderr directly for writing to stderr (#62) by chressie · 3 months ago master v1.1.1
  2. 6ce8ac9 glog: update minimum go version to go1.19 (#61) by chressie · 3 months ago
  3. c0f9e3d glog: don't use SIGABRT on platforms that don't support signals by chressie · 3 months ago
  4. 9c9801e glog: make zero value of vModuleFlag usable by chressie · 3 months ago
  5. 2cef961 glog: use strings.TrimSuffix by chressie · 3 months ago



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.

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