os file builtins refactored with the package 'file'

file/file.go

@@ -0,0 +1,46 @@
+// Copyright (c) 2024-2026 Celestino Amoroso (celestino.amoroso@gmail.com).
+// All rights reserved.
+
+// file.go
+package file
+
+import (
+	"os"
+
+	"git.portale-stac.it/go-pkg/expr/kern"
+)
+
+type Handle interface {
+	kern.Typer
+	GetFile() *os.File
+	GetName() string
+	Valid() bool
+	Close() error
+}
+
+type handleBase struct {
+	fh *os.File
+}
+
+func (h *handleBase) GetFile() *os.File {
+	return h.fh
+}
+
+func (h *handleBase) GetName() (name string) {
+	if h.fh != nil {
+		name = h.fh.Name()
+	}
+	return
+}
+
+func (h *handleBase) Valid() bool {
+	return h.fh != nil
+}
+
+func (h *handleBase) Close() (err error) {
+	if h.fh != nil {
+		err = h.fh.Close()
+		h.fh = nil
+	}
+	return
+}