/
fsnotify.go
83 lines (69 loc) · 1.35 KB
/
fsnotify.go
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package main
import (
"flag"
"fmt"
"log"
"os"
"github.com/fsnotify/fsnotify"
)
func NewWatcher(file string) {
watcher, err := fsnotify.NewWatcher()
if err != nil {
log.Fatal(err)
}
defer watcher.Close()
done := make(chan bool)
go func() {
for {
select {
case event := <-watcher.Events:
if event.Op&fsnotify.Write == fsnotify.Write {
log.Println("modified file:", event.Name)
} else if event.Op&fsnotify.Rename == fsnotify.Rename {
log.Println("rename file:", event.Name)
} else {
log.Println("event:", event)
}
case err := <-watcher.Errors:
log.Println("error:", err)
}
}
}()
err = watcher.Add(file)
if err != nil {
log.Fatal(err)
}
<-done
}
var Usage = func() {
fmt.Fprintf(os.Stdout, "Usage: %s filename\n\n", os.Args[0])
os.Exit(1)
}
// FileExists returns whether a file exists at a given filesystem path.
func FileExists(path string) (bool, error) {
_, err := os.Stat(path)
if err == nil {
return true, nil
}
if os.IsNotExist(err) {
return false, fmt.Errorf("not found: %s", path)
}
return false, err
}
var filename string
func init() {
flag.Usage = Usage
flag.Parse()
if flag.NArg() != 1 {
flag.Usage()
}
filename = flag.Arg(0)
if ret, err := FileExists(filename); !ret {
log.Println(err)
flag.Usage()
}
}
func main() {
filename := flag.Arg(0)
NewWatcher(filename)
}