Use only a single .tar archive because there are not enough IDE ports available in QEMU

.gitignore

@@ -1,4 +1,5 @@
 /*.nar
 /*.sizes
+/*.tar
 /signing-key.pub
 /vm-image

Makefile

@@ -8,21 +8,22 @@ all: hello.tar hello.sizes vm-image to-be-run-in-vm.sh Makefile
 	  vm-image-${tmp_image} \
 	  -drive format=raw,file=hello.sizes,if=ide,index=1,media=disk \
 	  -drive format=raw,file=to-be-run-in-vm.sh,if=ide,index=2,media=disk \
-	  -drive format=raw,file=hello.nar,if=ide,index=3,media=disk \
-	  # -drive format=raw,file=signing-key.pub,if=ide,index=4,media=disk
+	  -drive format=raw,file=hello.tar,if=ide,index=3,media=disk
 	rm vm-image-${tmp_image}
 
-%.sizes: %.nar signing-key.pub to-be-run-in-vm.sh Makefile
-	printf "%020d\\n%020d\\n%020d\\n%$$((512-((20+1)*3)-1))s\\n" \
+%.sizes: %.tar signing-key.pub to-be-run-in-vm.sh Makefile
+	printf "%020d\\n%020d\\n%$$((512-((20+1)*2)-1))s\\n" \
 	  "$$(wc -c "to-be-run-in-vm.sh" | sed -e 's/^[[:space:]]*\([0-9][0-9]*\)[[:space:]].*$$/\1/')" \
-	  "$$(wc -c "$*.nar" | sed -e 's/^[[:space:]]*\([0-9][0-9]*\)[[:space:]].*$$/\1/')" \
-	  "$$(wc -c "signing-key.pub" | sed -e 's/^[[:space:]]*\([0-9][0-9]*\)[[:space:]].*$$/\1/')" \
+	  "$$(wc -c "$*.tar" | sed -e 's/^[[:space:]]*\([0-9][0-9]*\)[[:space:]].*$$/\1/')" \
 	  "" \
 	  > $@
 
 %.nar: Makefile
 	guix archive --export --recursive '$*' > '$@'
 
+%.tar: %.nar signing-key.pub Makefile
+	tar -cf '$@' '$*.nar' signing-key.pub
+
 signing-key.pub: /etc/guix/signing-key.pub Makefile
 	cp '$<' '$@'
 	chmod +w '$@'

to-be-run-in-vm.sh

@@ -1,9 +1,8 @@
 #!/bin/sh
 
-echo LALALA
-{ read len_script; read len_nar; read len_key; } < /dev/sdb
-echo x $len_script y $len_nar z $len_key t
-head -c "$len_nar" /dev/sdd | sha1sum
-echo DONE
-# dd if=/dev/sde bs=1 count=$len_key | sha1sum
-#
+echo
+{ read len_script; read len_tar; } < /dev/sdb
+pwd
+head -c "$len_tar" /dev/sdd | tar -xf -
+sha1sum hello.nar
+sha1sum signing-key.pub