Add plan 9 support for osFileInfo

Signed-off-by: Ronald G Minnich <[email protected]>

Author: rminnich

file/file_other.go

@@ -1,4 +1,4 @@
-//go:build !windows && !darwin && !dragonfly && !freebsd && !linux && !nacl && !netbsd && !openbsd && !solaris && !wasm
+//go:build !windows && !darwin && !dragonfly && !freebsd && !linux && !nacl && !netbsd && !openbsd && !solaris && !wasm && !plan9
 
 package file
 

file/file_plan9.go

@@ -0,0 +1,12 @@
+package file
+
+import (
+	"os"
+)
+
+// getOSFileInfo returns file information on Unix.
+// There are no such fields on Plan 9 -- at least
+// of the Unix type. Plan 9 uids and gids are strings.
+func getOSFileInfo(info os.FileInfo) *FileInfo {
+	return nil
+}