diff --git a/polymer/eduke32/Makefile b/polymer/eduke32/Makefile
index 93dea7e6f..fd5ab744d 100644
--- a/polymer/eduke32/Makefile
+++ b/polymer/eduke32/Makefile
@@ -173,6 +173,7 @@ ifneq (0,$(LUNATIC))
                $(OBJ)/luaJIT_BC_dis_x86.$o \
                $(OBJ)/luaJIT_BC_dis_x64.$o \
                $(OBJ)/luaJIT_BC_savegame.$o \
+               $(OBJ)/luaJIT_BC_fs.$o \
     # TODO: remove debugging modules from release build
 
     # now, take care of having the necessary symbols (sector, wall, etc.) in the
diff --git a/polymer/eduke32/source/lunatic/defs.ilua b/polymer/eduke32/source/lunatic/defs.ilua
index cc9f03531..d3290b274 100644
--- a/polymer/eduke32/source/lunatic/defs.ilua
+++ b/polymer/eduke32/source/lunatic/defs.ilua
@@ -63,6 +63,8 @@ function decl(str, ...)
     ffi.cdef(str, ...)
 end
 
+lprivate.decl = decl
+
 -- Load the definitions common to the game's and editor's Lua interface.
 local defs_c = require("defs_common")
 local cansee = defs_c.cansee
@@ -1568,6 +1570,7 @@ local allowed_modules = {
     stat = require("stat"),
     bitar = require("bitar"),
     xmath = require("xmath"),
+    fs = require("fs"),
 
     con = con,
 }
@@ -2180,6 +2183,9 @@ G_.actor = actor
 G_.projectile = projectile
 G_.g_tile = g_tile
 
+-- A table that can be used for temporary data when debugging from the OSD.
+G_.d = {}
+
 
 ---=== Lunatic translator setup ===---
 
diff --git a/polymer/eduke32/source/lunatic/doc/lunacon.txt b/polymer/eduke32/source/lunatic/doc/lunacon.txt
index 3fd975221..587c63d14 100644
--- a/polymer/eduke32/source/lunatic/doc/lunacon.txt
+++ b/polymer/eduke32/source/lunatic/doc/lunacon.txt
@@ -330,7 +330,4 @@ predefined constants.
 Miscellaneous
 ^^^^^^^^^^^^^
 
-* gamevar flags 1024 (```NODEFAULT`'') and 131072 (```NORESET`'') are not
-  handled
-* mapstate handling in savegames is not yet implemented
 * not LunaCON-specific: `EVENT_INIT` is never reached as it runs before Lua state creation
diff --git a/polymer/eduke32/source/lunatic/doc/lunatic.txt b/polymer/eduke32/source/lunatic/doc/lunatic.txt
index 9ba2f3bcf..f4d37cf6e 100644
--- a/polymer/eduke32/source/lunatic/doc/lunatic.txt
+++ b/polymer/eduke32/source/lunatic/doc/lunatic.txt
@@ -97,6 +97,11 @@ CAUTION: If an attempt is made to create a new variable in the global
 environment or to assign any value to an existing variable, the behavior is
 undefined.
 
+For convenience of debugging from the command line (using the `lua` OSD
+command), the global environment contains a table `d` which is initially
+empty. It should only be used to temporarily store values of interest in a
+debugging session and should never be referenced from actual script code.
+
 Lua functions
 ~~~~~~~~~~~~~
 
@@ -1922,6 +1927,16 @@ run afterwards, possibly modifying the sprite.
 Returns the index of the spawned sprite on success.
 
 
+The `fs` module -- virtual file system facilities
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+[red]*DRAFT*
+
+===== `files = fs.listpath(path, mask)`
+
+Lists file names matching a wildcard `mask` which can be found under `path`.
+
+
 /////////////////
 APPENDICES FOLLOW
 /////////////////
diff --git a/polymer/eduke32/source/lunatic/dynsymlist b/polymer/eduke32/source/lunatic/dynsymlist
index 4326a4c7c..4f2948936 100644
--- a/polymer/eduke32/source/lunatic/dynsymlist
+++ b/polymer/eduke32/source/lunatic/dynsymlist
@@ -72,6 +72,10 @@ kclose;
 kread;
 klseek;
 
+pathsearchmode;
+klistfree;
+klistpath;
+
 dist;
 ldist;
 
@@ -184,6 +188,7 @@ luaJIT_BC_dump;
 luaJIT_BC_dis_x86;
 luaJIT_BC_dis_x64;
 luaJIT_BC_savegame;
+luaJIT_BC_fs;
 
 rand_jkiss_u32;
 rand_jkiss_dbl;
diff --git a/polymer/eduke32/source/lunatic/fs.lua b/polymer/eduke32/source/lunatic/fs.lua
new file mode 100644
index 000000000..58737da80
--- /dev/null
+++ b/polymer/eduke32/source/lunatic/fs.lua
@@ -0,0 +1,84 @@
+-- Virtual file system facilities for Lunatic
+
+local ffi = require("ffi")
+local C = ffi.C
+
+local decl = require("lprivate").decl
+
+local assert = assert
+local error = error
+local type = type
+
+----------
+
+decl[[
+int32_t pathsearchmode;
+
+typedef struct _CACHE1D_FIND_REC {
+	char *name;
+	int32_t type, source;
+	struct _CACHE1D_FIND_REC *next, *prev, *usera, *userb;
+} CACHE1D_FIND_REC;
+
+void klistfree(CACHE1D_FIND_REC *rec);
+CACHE1D_FIND_REC *klistpath(const char *path, const char *mask, int32_t type);
+]]
+
+
+-- The API table
+local fs = {}
+
+local CACHE1D = ffi.new[[
+struct {
+	static const int FIND_FILE = 1;
+	static const int FIND_DIR = 2;
+	static const int FIND_DRIVE = 4;
+
+	static const int OPT_NOSTACK = 0x100;
+
+	// the lower the number, the higher the priority
+	static const int SOURCE_DRIVE = 0;
+	static const int SOURCE_CURDIR = 1;
+	static const int SOURCE_PATH = 2;  // + path stack depth
+	static const int SOURCE_ZIP = 0x7ffffffe;
+	static const int SOURCE_GRP = 0x7fffffff;
+}
+]]
+
+-- files = fs.listpath(path, mask)
+-- TODO: filter by 'source' (path, zip and/or grp)
+-- TODO: directories too, so that one can list them recursively, for example
+function fs.listpath(path, mask)
+    if (path ~= nil and type(path)~="string") then
+        error("Invalid argument #1: must be nil or a string", 2)
+    end
+
+    if (type(mask) ~= "string") then
+        error("Invalid argument #2: must be a string", 2)
+    end
+
+    local opsm = C.pathsearchmode
+    C.pathsearchmode = 0
+    local rootrec = C.klistpath(path, mask, CACHE1D.FIND_FILE)
+    C.pathsearchmode = opsm
+
+    if (rootrec == nil) then
+        -- TODO: discern?
+        error("out of memory or failed listing path")
+    end
+
+    local files = {}
+
+    local rec = rootrec
+    while (rec ~= nil) do
+        assert(rec.name ~= nil)
+        files[#files+1] = ffi.string(rec.name)
+        rec = rec.next
+    end
+
+    C.klistfree(rootrec)
+
+    return files
+end
+
+return fs