diff --git a/src/RTEMS/base/rtems_init.c b/src/RTEMS/base/rtems_init.c
index 9e3a93394..d6fb4fcd2 100644
--- a/src/RTEMS/base/rtems_init.c
+++ b/src/RTEMS/base/rtems_init.c
@@ -15,7 +15,6 @@
 #include <stdlib.h>
 #include <string.h>
 #include <ctype.h>
-#include <unistd.h>
 #include <errno.h>
 #include <sys/termios.h>
 #include <sys/types.h>
@@ -31,6 +30,7 @@
 #include <epicsThread.h>
 #include <errlog.h>
 #include <logClient.h>
+#include <osiUnistd.h>
 #include <iocsh.h>
 
 /*
diff --git a/src/libCom/osi/os/default/osdEnv.c b/src/libCom/osi/os/default/osdEnv.c
index 9ff9cd08f..6f3771919 100644
--- a/src/libCom/osi/os/default/osdEnv.c
+++ b/src/libCom/osi/os/default/osdEnv.c
@@ -25,6 +25,7 @@
 #include <errlog.h>
 #include <cantProceed.h>
 #include <envDefs.h>
+#include <osiUnistd.h>
 #include "epicsFindSymbol.h"
 
 /*