glog: github.com/golang/glog Index | Files

package glog

import "github.com/golang/glog"

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")

Log output is buffered and written periodically using Flush. Programs should call Flush before exiting to guarantee all log output is written.

By default, all log statements write to files in a temporary directory. This package provides several flags that modify this behavior. As a result, flag.Parse must be called before any logging is done.

-logtostderr=false
	Logs are written to standard error instead of to files.
-alsologtostderr=false
	Logs are written to standard error as well as to files.
-stderrthreshold=ERROR
	Log events at or above this severity are logged to standard
	error as well as to files.
-log_dir=""
	Log files will be written to this directory instead of the
	default temporary directory.

Other flags provide aids to debugging.

-log_backtrace_at=""
	When set to a file and line number holding a logging statement,
	such as
		-log_backtrace_at=gopherflakes.go:234
	a stack trace will be written to the Info log whenever execution
	hits that statement. (Unlike with -vmodule, the ".go" must be
	present.)
-v=0
	Enable V-leveled logging at the specified level.
-vmodule=""
	The syntax of the argument is a comma-separated list of pattern=N,
	where pattern is a literal file name (minus the ".go" suffix) or
	"glob" pattern and N is a V level. For instance,
		-vmodule=gopher*=3
	sets the V level to 3 in all Go files whose names begin "gopher".

Index

Package Files

glog.go glog_file.go

Variables

var MaxSize uint64 = 1024 * 1024 * 1800

MaxSize is the maximum size of a log file in bytes.

var Stats struct {
    Info, Warning, Error OutputStats
}

Stats tracks the number of lines of output and number of bytes per severity level. Values must be read with atomic.LoadInt64.

func CopyStandardLogTo Uses

func CopyStandardLogTo(name string)

CopyStandardLogTo arranges for messages written to the Go "log" package's default logs to also appear in the Google logs for the named and lower severities. Subsequent changes to the standard log's default output location or format may break this behavior.

Valid names are "INFO", "WARNING", "ERROR", and "FATAL". If the name is not recognized, CopyStandardLogTo panics.

func Error Uses

func Error(args ...interface{})

Error logs to the ERROR, WARNING, and INFO logs. Arguments are handled in the manner of fmt.Print; a newline is appended if missing.

func ErrorDepth Uses

func ErrorDepth(depth int, args ...interface{})

ErrorDepth acts as Error but uses depth to determine which call frame to log. ErrorDepth(0, "msg") is the same as Error("msg").

func Errorf Uses

func Errorf(format string, args ...interface{})

Errorf logs to the ERROR, WARNING, and INFO logs. Arguments are handled in the manner of fmt.Printf; a newline is appended if missing.

func Errorln Uses

func Errorln(args ...interface{})

Errorln logs to the ERROR, WARNING, and INFO logs. Arguments are handled in the manner of fmt.Println; a newline is appended if missing.

func Exit Uses

func Exit(args ...interface{})

Exit logs to the FATAL, ERROR, WARNING, and INFO logs, then calls os.Exit(1). Arguments are handled in the manner of fmt.Print; a newline is appended if missing.

func ExitDepth Uses

func ExitDepth(depth int, args ...interface{})

ExitDepth acts as Exit but uses depth to determine which call frame to log. ExitDepth(0, "msg") is the same as Exit("msg").

func Exitf Uses

func Exitf(format string, args ...interface{})

Exitf logs to the FATAL, ERROR, WARNING, and INFO logs, then calls os.Exit(1). Arguments are handled in the manner of fmt.Printf; a newline is appended if missing.

func Exitln Uses

func Exitln(args ...interface{})

Exitln logs to the FATAL, ERROR, WARNING, and INFO logs, then calls os.Exit(1).

func Fatal Uses

func Fatal(args ...interface{})

Fatal logs to the FATAL, ERROR, WARNING, and INFO logs, including a stack trace of all running goroutines, then calls os.Exit(255). Arguments are handled in the manner of fmt.Print; a newline is appended if missing.

func FatalDepth Uses

func FatalDepth(depth int, args ...interface{})

FatalDepth acts as Fatal but uses depth to determine which call frame to log. FatalDepth(0, "msg") is the same as Fatal("msg").

func Fatalf Uses

func Fatalf(format string, args ...interface{})

Fatalf logs to the FATAL, ERROR, WARNING, and INFO logs, including a stack trace of all running goroutines, then calls os.Exit(255). Arguments are handled in the manner of fmt.Printf; a newline is appended if missing.

func Fatalln Uses

func Fatalln(args ...interface{})

Fatalln logs to the FATAL, ERROR, WARNING, and INFO logs, including a stack trace of all running goroutines, then calls os.Exit(255). Arguments are handled in the manner of fmt.Println; a newline is appended if missing.

func Flush Uses

func Flush()

Flush flushes all pending log I/O.

func Info Uses

func Info(args ...interface{})

Info logs to the INFO log. Arguments are handled in the manner of fmt.Print; a newline is appended if missing.

func InfoDepth Uses

func InfoDepth(depth int, args ...interface{})

InfoDepth acts as Info but uses depth to determine which call frame to log. InfoDepth(0, "msg") is the same as Info("msg").

func Infof Uses

func Infof(format string, args ...interface{})

Infof logs to the INFO log. Arguments are handled in the manner of fmt.Printf; a newline is appended if missing.

func Infoln Uses

func Infoln(args ...interface{})

Infoln logs to the INFO log. Arguments are handled in the manner of fmt.Println; a newline is appended if missing.

func Warning Uses

func Warning(args ...interface{})

Warning logs to the WARNING and INFO logs. Arguments are handled in the manner of fmt.Print; a newline is appended if missing.

func WarningDepth Uses

func WarningDepth(depth int, args ...interface{})

WarningDepth acts as Warning but uses depth to determine which call frame to log. WarningDepth(0, "msg") is the same as Warning("msg").

func Warningf Uses

func Warningf(format string, args ...interface{})

Warningf logs to the WARNING and INFO logs. Arguments are handled in the manner of fmt.Printf; a newline is appended if missing.

func Warningln Uses

func Warningln(args ...interface{})

Warningln logs to the WARNING and INFO logs. Arguments are handled in the manner of fmt.Println; a newline is appended if missing.

type Level Uses

type Level int32

Level specifies a level of verbosity for V logs. *Level implements flag.Value; the -v flag is of type Level and should be modified only through the flag.Value interface.

func (*Level) Get Uses

func (l *Level) Get() interface{}

Get is part of the flag.Value interface.

func (*Level) Set Uses

func (l *Level) Set(value string) error

Set is part of the flag.Value interface.

func (*Level) String Uses

func (l *Level) String() string

String is part of the flag.Value interface.

type OutputStats Uses

type OutputStats struct {
    // contains filtered or unexported fields
}

OutputStats tracks the number of output lines and bytes written.

func (*OutputStats) Bytes Uses

func (s *OutputStats) Bytes() int64

Bytes returns the number of bytes written.

func (*OutputStats) Lines Uses

func (s *OutputStats) Lines() int64

Lines returns the number of lines written.

type Verbose Uses

type Verbose bool

Verbose is a boolean type that implements Infof (like Printf) etc. See the documentation of V for more information.

func V Uses

func V(level Level) Verbose

V reports whether verbosity at the call site is at least the requested level. The returned value is a boolean of type Verbose, which implements Info, Infoln and Infof. These methods will write to the Info log if called. Thus, one may write either

if glog.V(2) { glog.Info("log this") }

or

glog.V(2).Info("log this")

The second form is shorter but the first is cheaper if logging is off because it does not evaluate its arguments.

Whether an individual call to V generates a log record depends on the setting of the -v and --vmodule flags; both are off by default. If the level in the call to V is at least the value of -v, or of -vmodule for the source file containing the call, the V call will log.

func (Verbose) Info Uses

func (v Verbose) Info(args ...interface{})

Info is equivalent to the global Info function, guarded by the value of v. See the documentation of V for usage.

func (Verbose) Infof Uses

func (v Verbose) Infof(format string, args ...interface{})

Infof is equivalent to the global Infof function, guarded by the value of v. See the documentation of V for usage.

func (Verbose) Infoln Uses

func (v Verbose) Infoln(args ...interface{})

Infoln is equivalent to the global Infoln function, guarded by the value of v. See the documentation of V for usage.

Package glog imports 16 packages (graph) and is imported by 23265 packages. Updated 2017-09-22. Refresh now. Tools for package owners.