diff --git a/web2c/ptexdir/kanji.h b/web2c/ptexdir/kanji.h
index 9c8f43b..2a339ce 100644
--- a/web2c/ptexdir/kanji.h
+++ b/web2c/ptexdir/kanji.h
@@ -15,6 +15,10 @@
 #define KANJI
 #endif
 
+#include <kpathsea/knj.h>
+#define not_kanji_char_seq(a,b) (!(is_cp932_system && isknj(a) && isknj2(b)))
+#define notkanjicharseq not_kanji_char_seq
+
 #if !defined(WIN32)
 extern int sjisterminal;
 #endif
diff --git a/web2c/ptexdir/ptex-base.ch b/web2c/ptexdir/ptex-base.ch
index 5bac489..fabc997 100644
--- a/web2c/ptexdir/ptex-base.ch
+++ b/web2c/ptexdir/ptex-base.ch
@@ -114,6 +114,7 @@ var k,@!l:KANJI_code; {small indices or counters}
   pseudoprinting}
 @!trick_buf2:array[0..ssup_error_line] of 0..2; {pTeX: buffer for KANJI}
 @!kcode_pos: 0..2; {pTeX: denotes whether first byte or second byte of KANJI}
+@!prev_char: ASCII_code;
 @z
 
 @x [5.55] l.1519 - pTeX: Initialize the kcode_pos
@@ -2406,6 +2407,37 @@ else if (cur_cmd>active_char)or(cur_chr>255) then
   end;
 @z
 
+@x pTeX for Windows, treat filename with 0x5c
+@p procedure begin_name;
+begin area_delimiter:=0; ext_delimiter:=0; quoted_filename:=false;
+end;
+@y
+@p procedure begin_name;
+begin area_delimiter:=0; ext_delimiter:=0; quoted_filename:=false; prev_char:=0;
+end;
+@z
+
+@x pTeX for Windows, treat filename with 0x5c
+else  begin str_room(1); append_char(c); {contribute |c| to the current string}
+  if IS_DIR_SEP(c) then
+    begin area_delimiter:=cur_length; ext_delimiter:=0;
+    end
+  else if c="." then ext_delimiter:=cur_length;
+  more_name:=true;
+  end;
+end;
+@y
+else  begin str_room(1); append_char(c); {contribute |c| to the current string}
+  if (IS_DIR_SEP(c)and(not_kanji_char_seq(prev_char,c))) then
+    begin area_delimiter:=cur_length; ext_delimiter:=0;
+    end
+  else if c="." then ext_delimiter:=cur_length;
+  more_name:=true;
+  end;
+  prev_char:=c;
+end;
+@z
+
 @x [29.526] l.10668 - pTeX: scan file name
 loop@+begin if (cur_cmd>other_char)or(cur_chr>255) then {not a character}
     begin back_input; goto done;
diff --git a/web2c/ptexdir/ptex.defines b/web2c/ptexdir/ptex.defines
index b8729a1..5cffc9c 100644
--- a/web2c/ptexdir/ptex.defines
+++ b/web2c/ptexdir/ptex.defines
@@ -20,6 +20,7 @@
 @define function fromSJIS ();
 @define function fromKUTEN ();
 
+@define function notkanjicharseq ();
 @define function checkkanji ();
 @define function ischarascii ();
 @define function ischarkanji ();