github.com/ethereumproject/go-ethereum@v5.5.2+incompatible/logger/example_test.go (about) 1 // Copyright 2014 The go-ethereum Authors 2 // This file is part of the go-ethereum library. 3 // 4 // The go-ethereum library is free software: you can redistribute it and/or modify 5 // it under the terms of the GNU Lesser General Public License as published by 6 // the Free Software Foundation, either version 3 of the License, or 7 // (at your option) any later version. 8 // 9 // The go-ethereum library is distributed in the hope that it will be useful, 10 // but WITHOUT ANY WARRANTY; without even the implied warranty of 11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 // GNU Lesser General Public License for more details. 13 // 14 // You should have received a copy of the GNU Lesser General Public License 15 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>. 16 17 package logger 18 19 import "os" 20 21 func ExampleLogger() { 22 logger := NewLogger("TAG") 23 logger.Infoln("so awesome") // prints [TAG] so awesome 24 logger.Infof("this %q is raw", "coin") // prints [TAG] this "coin" is raw 25 } 26 27 func ExampleLogSystem() { 28 filename := "test.log" 29 file, _ := os.OpenFile(filename, os.O_RDWR|os.O_CREATE, os.ModePerm) 30 fileLog := NewStdLogSystem(file, 0, WarnLevel) 31 AddLogSystem(fileLog) 32 33 stdoutLog := NewStdLogSystem(os.Stdout, 0, WarnLevel) 34 AddLogSystem(stdoutLog) 35 36 NewLogger("TAG").Warnln("reactor meltdown") // writes to both logs 37 }