diff --git a/master/Makefile.am b/master/Makefile.am
index 65371f72..1a0ef30a 100644
--- a/master/Makefile.am
+++ b/master/Makefile.am
@@ -60,6 +60,7 @@ noinst_HEADERS = \
 	reg_request.c reg_request.h \
 	rtdm-ioctl.c \
 	rtdm.c rtdm.h \
+	rtdm_details.h \
 	rtdm_xenomai_v3.c \
 	sdo.c sdo.h \
 	sdo_entry.c sdo_entry.h \
diff --git a/master/rtdm.c b/master/rtdm.c
index eac71eea..e5e73e09 100644
--- a/master/rtdm.c
+++ b/master/rtdm.c
@@ -33,6 +33,7 @@
 #include "master.h"
 #include "ioctl.h"
 #include "rtdm.h"
+#include "rtdm_details.h"
 
 /** Set to 1 to enable device operations debugging.
  */
@@ -40,15 +41,6 @@
 
 /****************************************************************************/
 
-/** Context structure for an open RTDM file handle.
- */
-typedef struct {
-    rtdm_user_info_t *user_fd; /**< RTDM user data. */
-    ec_ioctl_context_t ioctl_ctx; /**< Context structure. */
-} ec_rtdm_context_t;
-
-/****************************************************************************/
-
 int ec_rtdm_open(struct rtdm_dev_context *, rtdm_user_info_t *, int);
 int ec_rtdm_close(struct rtdm_dev_context *, rtdm_user_info_t *);
 int ec_rtdm_ioctl(struct rtdm_dev_context *, rtdm_user_info_t *,
diff --git a/master/rtdm_details.h b/master/rtdm_details.h
new file mode 100644
index 00000000..8b8c0f3c
--- /dev/null
+++ b/master/rtdm_details.h
@@ -0,0 +1,57 @@
+/*****************************************************************************
+ *
+ *  Copyright (C)      2024  Bjarne von Horn <vh@igh.de>
+ *
+ *  This file is part of the IgH EtherCAT master.
+ *
+ *  The IgH EtherCAT master is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License as published
+ *  by the Free Software Foundation; version 2 of the License.
+ *
+ *  The IgH EtherCAT master is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+ *  Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with the IgH EtherCAT master. If not, see <http://www.gnu.org/licenses/>.
+ *
+ *  The license mentioned above concerns the source code only. Using the
+ *  EtherCAT technology and brand is only permitted in compliance with the
+ *  industrial property and similar rights of Beckhoff Automation GmbH.
+ *
+ ****************************************************************************/
+
+
+#ifndef __EC_RTDM_DETAILS_H__
+#define __EC_RTDM_DETAILS_H__
+
+#include "../config.h"
+
+#include <linux/kernel.h>
+
+#ifdef EC_RTDM_XENOMAI_V3
+
+#include <rtdm/driver.h>
+#define EC_RTDM_USERFD_T struct rtdm_fd
+
+#else // EC_RTDM_XENOMAI_V3
+
+#include <rtdm/rtdm_driver.h>
+
+#define EC_RTDM_USERFD_T rtdm_user_info_t
+
+#endif
+
+/****************************************************************************/
+
+/** Context structure for an open RTDM file handle.
+ */
+typedef struct ec_rtdm_context {
+    EC_RTDM_USERFD_T *user_fd; /**< RTDM user data. */
+    ec_ioctl_context_t ioctl_ctx; /**< Context structure. */
+} ec_rtdm_context_t;
+
+/****************************************************************************/
+
+#endif  // __EC_RTDM_DETAILS_H__
diff --git a/master/rtdm_xenomai_v3.c b/master/rtdm_xenomai_v3.c
index 0bc90862..4a58950a 100644
--- a/master/rtdm_xenomai_v3.c
+++ b/master/rtdm_xenomai_v3.c
@@ -37,16 +37,12 @@
 #include "master.h"
 #include "ioctl.h"
 #include "rtdm.h"
+#include "rtdm_details.h"
 
 /** Set to 1 to enable device operations debugging.
  */
 #define DEBUG_RTDM 0
 
-struct ec_rtdm_context {
-	struct rtdm_fd *user_fd;
-	ec_ioctl_context_t ioctl_ctx;	/**< Context structure. */
-};
-
 static int ec_rtdm_open(struct rtdm_fd *fd, int oflags)
 {
 	struct ec_rtdm_context *ctx = rtdm_fd_to_private(fd);