zones: introduce Machine.OpenFile()

Signed-off-by: Alejandro Mery <amery@jpi.io>

pkg/zones/machine_file.go

@@ -8,6 +8,14 @@ import (
 	fs "github.com/hack-pad/hackpadfs"
 )
 
+// OpenFile opens a file on the machine's config directory with the specified flags
+func (m *Machine) OpenFile(name string, flags int, args ...any) (fs.File, error) {
+	base := m.zone.zones.dir
+	fullName := m.getFilename(name, args...)
+
+	return fs.OpenFile(base, fullName, flags, 0644)
+}
+
 // RemoveFile deletes a file from the machine's config directory
 func (m *Machine) RemoveFile(name string, args ...any) error {
 	base := m.zone.zones.dir