diff --git a/include/device.h b/include/device.h
index faf674665..68b1c807a 100644
--- a/include/device.h
+++ b/include/device.h
@@ -55,6 +55,8 @@ unsigned char getfirstdevice (void);
 
 unsigned char __fastcall__ getnextdevice (unsigned char device);
 
+unsigned char getcurrentdevice (void);
+
 char* __fastcall__ getdevicedir (unsigned char device, char* buf, size_t size);
 
 
diff --git a/libsrc/apple2/Makefile b/libsrc/apple2/Makefile
index ad4573ac3..9f14a081c 100644
--- a/libsrc/apple2/Makefile
+++ b/libsrc/apple2/Makefile
@@ -61,6 +61,7 @@ S_OBJS=	_scrsize.o	\
 	cputc.o		\
 	crt0.o		\
 	ctype.o		\
+	curdevice.o	\
 	cvline.o	\
 	devicedir.o	\
 	dioclose.o	\
diff --git a/libsrc/apple2/curdevice.s b/libsrc/apple2/curdevice.s
new file mode 100644
index 000000000..9781b8ad0
--- /dev/null
+++ b/libsrc/apple2/curdevice.s
@@ -0,0 +1,27 @@
+;
+; Oliver Schmidt, 2012-10-21
+;
+; unsigned char getcurrentdevice (void);
+;
+
+        .export         _getcurrentdevice
+        .import         __dos_type
+
+        .include        "mli.inc"
+
+_getcurrentdevice:
+
+        ; Use unit number of most recent accessed device
+        lda     DEVNUM
+        lsr
+        lsr
+        lsr
+        lsr
+
+        ; Check for ProDOS 8
+        ldx     __dos_type
+        bne     :+
+        lda     #$FF            ; INVALID_DEVICE
+
+:       ldx     #$00
+        rts
diff --git a/libsrc/apple2enh/Makefile b/libsrc/apple2enh/Makefile
index 0c564d465..02c6abd68 100644
--- a/libsrc/apple2enh/Makefile
+++ b/libsrc/apple2enh/Makefile
@@ -64,6 +64,7 @@ S_OBJS=	_scrsize.o	\
 	cputc.o		\
 	crt0.o		\
 	ctype.o		\
+	curdevice.o	\
 	cvline.o	\
 	devicedir.o	\
 	dioclose.o	\
diff --git a/libsrc/cbm/Makefile b/libsrc/cbm/Makefile
index 99753dd97..fa64e4f7c 100644
--- a/libsrc/cbm/Makefile
+++ b/libsrc/cbm/Makefile
@@ -68,6 +68,7 @@ S_OBJS =	c_acptr.o	\
 		close.o		\
 		closedir.o	\
 		ctype.o		\
+		curdevice.o	\
 		cvline.o	\
 		devicedir.o	\
 		dir.o		\
diff --git a/libsrc/cbm/curdevice.s b/libsrc/cbm/curdevice.s
new file mode 100644
index 000000000..8c2f7a866
--- /dev/null
+++ b/libsrc/cbm/curdevice.s
@@ -0,0 +1,19 @@
+;
+; Oliver Schmidt, 2012-10-21
+;
+; unsigned char getcurrentdevice (void);
+;
+
+        .export         _getcurrentdevice
+        .import         curunit
+
+;------------------------------------------------------------------------------
+; _getcurrentdevice
+
+.proc   _getcurrentdevice
+
+        lda     curunit
+        ldx     #$00
+        rts
+
+.endproc