--- a/libinterp/corefcn/file-io.cc	Wed Nov 24 12:01:52 2021 -0500
+++ b/libinterp/corefcn/file-io.cc	Wed Nov 24 11:02:23 2021 -0500
@@ -67,7 +67,6 @@
 #include "defun.h"
 #include "error.h"
 #include "errwarn.h"
-#include "file-io.h"
 #include "interpreter-private.h"
 #include "interpreter.h"
 #include "load-path.h"
@@ -3253,24 +3252,4 @@
   return const_value ("stderr", args, streams.stderr_file ());
 }
 
-// Deprecated variables and functions.
-
-// Remove when corresponding global deprecated function is removed.
-void mark_for_deletion_deprecated (const std::string& file)
-{
-  octave::interpreter& interp
-    = octave::__get_interpreter__ ("mark_for_deletion");
-
-  interp.mark_for_deletion (file);
-}
-
-// Remove when corresponding global deprecated function is removed.
-void cleanup_tmp_files_deprecated (void)
-{
-  octave::interpreter& interp
-    = octave::__get_interpreter__ ("cleanup_tmp_files");
-
-  interp.cleanup_tmp_files ();
-}
-
 OCTAVE_NAMESPACE_END

--- a/libinterp/corefcn/file-io.h	Wed Nov 24 12:01:52 2021 -0500
+++ b/libinterp/corefcn/file-io.h	Wed Nov 24 11:02:23 2021 -0500
@@ -23,27 +23,9 @@
 //
 ////////////////////////////////////////////////////////////////////////
 
-// Written by John C. Campbell <jcc@bevo.che.wisc.edu>
-
 #if ! defined (octave_file_io_h)
 #define octave_file_io_h 1
 
-#include "octave-config.h"
-
-#include <string>
-
-OCTAVE_NAMESPACE_BEGIN
-
-// Use this function internally until the function that uses it is
-// removed.  Remove when corresponding global deprecated function is
-// removed.
-extern void mark_for_deletion_deprecated (const std::string&);
-
-// Use this function internally until the function that uses it is
-// removed.  Remove when corresponding global deprecated function is
-// removed.
-extern void cleanup_tmp_files_deprecated (void);
-
-OCTAVE_NAMESPACE_END
+#warning "file-io.h was deprecated in Octave 8 and will be removed in a future version."
 
 #endif