// +build !windows
package dirlock
import (
"fmt"
"os"
"syscall"
)
type DirLock struct { dir string
f *os.File
}
func New(dir string) *DirLock { return &DirLock{ dir: dir,
}
}
func (l *DirLock) Lock() error { f, err := os.Open(l.dir)
if err != nil { return err
}
l.f = f
err = syscall.Flock(int(f.Fd()), syscall.LOCK_EX|syscall.LOCK_NB)
if err != nil { return fmt.Errorf("cannot flock directory %s - %s", l.dir, err) }
return nil
}
func (l *DirLock) Unlock() error { defer l.f.Close()
return syscall.Flock(int(l.f.Fd()), syscall.LOCK_UN)
}