tail/cmd/gotail/gotail.go

65 lines
1.4 KiB
Go

// Copyright (c) 2013 ActiveState Software Inc. All rights reserved.
package main
import (
"flag"
"fmt"
"github.com/hpcloud/tail"
"os"
)
func args2config() (tail.Config, int64) {
config := tail.Config{Follow: true}
n := int64(0)
maxlinesize := int(0)
flag.Int64Var(&n, "n", 0, "tail from the last Nth location")
flag.IntVar(&maxlinesize, "max", 0, "max line size")
flag.BoolVar(&config.Follow, "f", false, "wait for additional data to be appended to the file")
flag.BoolVar(&config.ReOpen, "F", false, "follow, and track file rename/rotation")
flag.BoolVar(&config.Poll, "p", false, "use polling, instead of inotify")
flag.Parse()
if config.ReOpen {
config.Follow = true
}
config.MaxLineSize = maxlinesize
return config, n
}
func main() {
config, n := args2config()
if flag.NFlag() < 1 {
fmt.Println("need one or more files as arguments")
os.Exit(1)
}
if n != 0 {
config.Location = &tail.SeekInfo{-n, os.SEEK_END}
}
done := make(chan bool)
for _, filename := range flag.Args() {
go tailFile(filename, config, done)
}
for _, _ = range flag.Args() {
<-done
}
}
func tailFile(filename string, config tail.Config, done chan bool) {
defer func() { done <- true }()
t, err := tail.TailFile(filename, config)
if err != nil {
fmt.Println(err)
return
}
for line := range t.Lines {
fmt.Println(line.Text)
}
err = t.Wait()
if err != nil {
fmt.Println(err)
}
}