diff --git a/test/mbox.c b/test/mbox.c
index 3dc1611..6c62ddb 100644
--- a/test/mbox.c
+++ b/test/mbox.c
@@ -87,6 +87,24 @@
 	return rc;
 }
 
+void mbox_rspcpy(struct mbox_context *context, struct mbox_msg *msg)
+{
+	struct stat details;
+	uint8_t *map;
+	int fd;
+
+	fd = context->fds[MBOX_FD].fd;
+	fstat(fd, &details);
+
+	map = mmap(NULL, details.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+	assert(map != MAP_FAILED);
+	assert(details.st_size >= (RESPONSE_OFFSET + RESPONSE_SIZE));
+
+	memcpy(msg, &map[RESPONSE_OFFSET], RESPONSE_SIZE);
+
+	munmap(map, details.st_size);
+}
+
 int mbox_command_write(struct mbox_context *context, const uint8_t *command,
 		size_t len)
 {
diff --git a/test/mbox.h b/test/mbox.h
index 5b89790..4344622 100644
--- a/test/mbox.h
+++ b/test/mbox.h
@@ -7,8 +7,9 @@
 #include <stddef.h>
 #include <stdint.h>
 
-#include "../common.h"
-#include "../mbox.h"
+#include "common.h"
+#include "mbox.h"
+#include "mboxd_msg.h"
 
 #include "tmpf.h"
 
@@ -19,6 +20,8 @@
 
 void mbox_dump(struct mbox_context *context);
 
+void mbox_rspcpy(struct mbox_context *context, struct mbox_msg *msg);
+
 int mbox_cmp(struct mbox_context *context, const uint8_t *expected, size_t len);
 
 int mbox_command_write(struct mbox_context *context, const uint8_t *command,