package afero import ( "os" "syscall" "time" ) type ReadOnlyFilter struct { } func NewReadonlyFilter() Fs { return &ReadOnlyFilter{} } func (r *ReadOnlyFilter) Chtimes(n string, a, m time.Time) error { return syscall.EPERM } func (r *ReadOnlyFilter) Chmod(n string, m os.FileMode) error { return syscall.EPERM } func (r *ReadOnlyFilter) Name() string { return "readOnlyFilter" } func (r *ReadOnlyFilter) Stat(name string) (os.FileInfo, error) { return nil, nil } func (r *ReadOnlyFilter) Rename(o, n string) error { return syscall.EPERM } func (r *ReadOnlyFilter) RemoveAll(p string) error { return syscall.EPERM } func (r *ReadOnlyFilter) Remove(n string) error { return syscall.EPERM } func (r *ReadOnlyFilter) OpenFile(name string, flag int, perm os.FileMode) (File, error) { if flag&(os.O_WRONLY|syscall.O_RDWR|os.O_APPEND|os.O_CREATE|os.O_TRUNC) != 0 { return nil, syscall.EPERM } return nil, nil } func (r *ReadOnlyFilter) Open(n string) (File, error) { return nil, nil } func (r *ReadOnlyFilter) Mkdir(n string, p os.FileMode) error { return syscall.EPERM } func (r *ReadOnlyFilter) MkdirAll(n string, p os.FileMode) error { return syscall.EPERM } func (r *ReadOnlyFilter) Create(n string) (File, error) { return nil, syscall.EPERM }