diff --git a/emul/Makefile b/emul/Makefile
index 1620026..47b6c8d 100644
--- a/emul/Makefile
+++ b/emul/Makefile
@@ -13,20 +13,20 @@ $(BLKPACK):
 $(BLKUNPACK): $(BLKPACK)
 
 stage: stage.c $(OBJS)
-	$(CC) stage.c -DFBIN_PATH=\"`pwd`/forth.bin\" -DBLKFS_PATH=\"`pwd`/blkfs\" $(OBJS) -o $@
+	$(CC) stage.c $(OBJS) -o $@
 
 blkfs: $(BLKPACK)
 	$(BLKPACK) ../blk > $@
 
 forth: forth.c $(OBJS)
-	$(CC) forth.c -DFBIN_PATH=\"`pwd`/forth.bin\" -DBLKFS_PATH=\"`pwd`/blkfs\" $(OBJS) -lncurses -o $@
+	$(CC) forth.c $(OBJS) -lncurses -o $@
 
 libz80/libz80.o: libz80/z80.c
 	$(MAKE) -C libz80/codegen opcodes
 	$(CC) -Wall -ansi -g -c -o libz80/libz80.o libz80/z80.c
 
 emul.o: emul.c
-	$(CC) -c -o emul.o emul.c
+	$(CC) -DFBIN_PATH=\"`pwd`/forth.bin\" -DBLKFS_PATH=\"`pwd`/blkfs\" -c -o emul.o emul.c
 
 
 .PHONY: updatebootstrap
diff --git a/emul/emul.c b/emul/emul.c
index 4cc0aec..b4efb34 100644
--- a/emul/emul.c
+++ b/emul/emul.c
@@ -1,13 +1,26 @@
-/* Common code between shell, zasm and runbin.
+/* Common code between forth and stage binaries.
 
 They all run on the same kind of virtual machine: A z80 CPU, 64K of RAM/ROM.
 */
 
 #include <string.h>
 #include "emul.h"
+// Port for block reads. Write 2 bytes, MSB first, on that port and then
+// read 1024 bytes from the DATA port.
+#define BLK_PORT 0x03
+#define BLKDATA_PORT 0x04
+
+#ifndef BLKFS_PATH
+#error BLKFS_PATH needed
+#endif
+#ifndef FBIN_PATH
+#error FBIN_PATH needed
+#endif
 
 static Machine m;
 static ushort traceval = 0;
+static uint16_t blkid = 0;
+static FILE *blkfp;
 
 static uint8_t io_read(int unused, uint16_t addr)
 {
@@ -32,6 +45,23 @@ static void io_write(int unused, uint16_t addr, uint8_t val)
     }
 }
 
+static void iowr_blk(uint8_t val)
+{
+    blkid <<= 8;
+    blkid |= val;
+    fseek(blkfp, blkid*1024, SEEK_SET);
+}
+
+static uint8_t iord_blkdata()
+{
+    return getc(blkfp);
+}
+
+static void iowr_blkdata(uint8_t val)
+{
+    putc(val, blkfp);
+}
+
 static uint8_t mem_read(int unused, uint16_t addr)
 {
     return m.mem[addr];
@@ -50,7 +80,26 @@ static void mem_write(int unused, uint16_t addr, uint8_t val)
 
 Machine* emul_init()
 {
+    fprintf(stderr, "Using blkfs %s\n", BLKFS_PATH);
+    blkfp = fopen(BLKFS_PATH, "r+");
+    if (!blkfp) {
+        fprintf(stderr, "Can't open\n");
+        return NULL;
+    }
+    // initialize memory
     memset(m.mem, 0, 0x10000);
+    FILE *bfp = fopen(FBIN_PATH, "r");
+    if (!bfp) {
+        fprintf(stderr, "Can't open forth.bin\n");
+        return NULL;
+    }
+    int i = 0;
+    int c = getc(bfp);
+    while (c != EOF) {
+        m.mem[i++] = c;
+        c = getc(bfp);
+    }
+    fclose(bfp);
     m.ramstart = 0;
     m.minsp = 0xffff;
     m.maxix = 0;
@@ -63,9 +112,16 @@ Machine* emul_init()
     m.cpu.memWrite = mem_write;
     m.cpu.ioRead = io_read;
     m.cpu.ioWrite = io_write;
+    m.iowr[BLK_PORT] = iowr_blk;
+    m.iord[BLKDATA_PORT] = iord_blkdata;
+    m.iowr[BLKDATA_PORT] = iowr_blkdata;
     return &m;
 }
 
+void emul_deinit()
+{
+    fclose(blkfp);
+}
 
 bool emul_step()
 {
diff --git a/emul/emul.h b/emul/emul.h
index cf41c1a..5bacb9b 100644
--- a/emul/emul.h
+++ b/emul/emul.h
@@ -29,6 +29,7 @@ typedef enum {
 } Tristate;
 
 Machine* emul_init();
+void emul_deinit();
 bool emul_step();
 bool emul_steps(unsigned int steps);
 void emul_loop();
diff --git a/emul/forth.c b/emul/forth.c
index 3965599..02ff75d 100644
--- a/emul/forth.c
+++ b/emul/forth.c
@@ -4,12 +4,6 @@
 #include <curses.h>
 #include <termios.h>
 #include "emul.h"
-#ifndef FBIN_PATH
-#error FBIN_PATH needed
-#endif
-#ifndef BLKFS_PATH
-#error BLKFS_PATH needed
-#endif
 
 // in sync with glue.asm
 #define RAMSTART 0x900
@@ -23,9 +17,7 @@
 #define BLKDATA_PORT 0x04
 
 static FILE *fp;
-static FILE *blkfp;
 static int retcode = 0;
-static uint16_t blkid = 0;
 
 static uint8_t iord_stdio()
 {
@@ -57,63 +49,20 @@ static void iowr_ret(uint8_t val)
     retcode = val;
 }
 
-static void iowr_blk(uint8_t val)
-{
-    blkid <<= 8;
-    blkid |= val;
-    fseek(blkfp, blkid*1024, SEEK_SET);
-}
-
-static uint8_t iord_blkdata()
-{
-    uint8_t res = 0;
-    int c = getc(blkfp);
-    if (c != EOF) {
-        res = c;
-    }
-    return res;
-}
-
-static void iowr_blkdata(uint8_t val)
-{
-    putc(val, blkfp);
-}
-
 int run()
 {
-    fprintf(stderr, "Using blkfs %s\n", BLKFS_PATH);
-    blkfp = fopen(BLKFS_PATH, "r+");
-    if (!blkfp) {
-        fprintf(stderr, "Can't open\n");
+    Machine *m = emul_init();
+    if (m == NULL) {
         return 1;
     }
-    Machine *m = emul_init();
     m->ramstart = RAMSTART;
     m->iord[STDIO_PORT] = iord_stdio;
     m->iowr[STDIO_PORT] = iowr_stdio;
     m->iowr[RET_PORT] = iowr_ret;
-    m->iowr[BLK_PORT] = iowr_blk;
-    m->iord[BLKDATA_PORT] = iord_blkdata;
-    m->iowr[BLKDATA_PORT] = iowr_blkdata;
-    // initialize memory
-    FILE *bfp = fopen(FBIN_PATH, "r");
-    if (!bfp) {
-        fprintf(stderr, "Can't open forth.bin\n");
-        return 1;
-    }
-    int i = 0;
-    int c = getc(bfp);
-    while (c != EOF) {
-        m->mem[i++] = c;
-        c = getc(bfp);
-    }
-    fclose(bfp);
     // Run!
     while (emul_step());
 
-    if (blkfp != NULL) {
-        fclose(blkfp);
-    }
+    emul_deinit();
     return retcode;
 }
 
diff --git a/emul/stage.c b/emul/stage.c
index cc38d7e..fe00dea 100644
--- a/emul/stage.c
+++ b/emul/stage.c
@@ -2,12 +2,6 @@
 #include <stdio.h>
 #include <unistd.h>
 #include "emul.h"
-#ifndef FBIN_PATH
-#error FBIN_PATH needed
-#endif
-#ifndef BLKFS_PATH
-#error BLKFS_PATH needed
-#endif
 
 /* Staging binaries
 
@@ -29,10 +23,6 @@ trouble of compiling defs to binary.
 // To know which part of RAM to dump, we listen to port 2, which at the end of
 // its compilation process, spits its HERE addr to port 2 (MSB first)
 #define HERE_PORT 0x02
-// Port for block reads. Write 2 bytes, MSB first, on that port and then
-// read 1024 bytes from the DATA port.
-#define BLK_PORT 0x03
-#define BLKDATA_PORT 0x04
 
 static int running;
 // We support double-pokes, that is, a first poke to tell where to start the
@@ -40,8 +30,6 @@ static int running;
 // then ending HERE and we start at sizeof(KERNEL).
 static uint16_t start_here = 0;
 static uint16_t end_here = 0;
-static uint16_t blkid = 0;
-static FILE *blkfp;
 
 static uint8_t iord_stdio()
 {
@@ -65,46 +53,16 @@ static void iowr_here(uint8_t val)
     end_here |= val;
 }
 
-static void iowr_blk(uint8_t val)
-{
-    blkid <<= 8;
-    blkid |= val;
-    fseek(blkfp, blkid*1024, SEEK_SET);
-}
-
-static uint8_t iord_blkdata()
-{
-    return getc(blkfp);
-}
-
 int main(int argc, char *argv[])
 {
-    fprintf(stderr, "Using blkfs %s\n", BLKFS_PATH);
-    blkfp = fopen(BLKFS_PATH, "r+");
-    if (!blkfp) {
-        fprintf(stderr, "Can't open\n");
+    Machine *m = emul_init();
+    if (m == NULL) {
         return 1;
     }
-    Machine *m = emul_init();
     m->ramstart = RAMSTART;
     m->iord[STDIO_PORT] = iord_stdio;
     m->iowr[STDIO_PORT] = iowr_stdio;
     m->iowr[HERE_PORT] = iowr_here;
-    m->iowr[BLK_PORT] = iowr_blk;
-    m->iord[BLKDATA_PORT] = iord_blkdata;
-    // initialize memory
-    FILE *bfp = fopen(FBIN_PATH, "r");
-    if (!bfp) {
-        fprintf(stderr, "Can't open forth.bin\n");
-        return 1;
-    }
-    int i = 0;
-    int c = getc(bfp);
-    while (c != EOF) {
-        m->mem[i++] = c;
-        c = getc(bfp);
-    }
-    fclose(bfp);
     // Run!
     running = 1;
 
@@ -114,6 +72,7 @@ int main(int argc, char *argv[])
     for (int i=start_here; i<end_here; i++) {
         putchar(m->mem[i]);
     }
+    emul_deinit();
     emul_printdebug();
     return 0;
 }