===================================================================
RCS file: /cvs2/dgamelaunch-openbsd/configure.ac,v
retrieving revision 1.3
retrieving revision 1.4
diff -u -p -r1.3 -r1.4
--- dgamelaunch-openbsd/configure.ac	2021/03/14 19:12:44	1.3
+++ dgamelaunch-openbsd/configure.ac	2021/03/16 10:10:55	1.4
@@ -161,6 +161,8 @@ AC_ARG_ENABLE(shmem,
 [enable_shmem=yes], [])
 
 if test "$enable_shmem" = yes; then
+   AS_IF([ test "$(uname -s)" = "OpenBSD" ],
+   	[AC_MSG_ERROR([enable-shmem is not implemented for this platform.])])
    AC_CHECK_HEADERS([semaphore.h], [], [AC_MSG_ERROR([semaphore.h not found.])], [])
    AC_CHECK_HEADERS([sys/ipc.h], [], [AC_MSG_ERROR([sys/ipc.h not found.])], [])
    AC_CHECK_HEADERS([sys/shm.h], [], [AC_MSG_ERROR([sys/shm.h not found.])], [])