diff --git a/cpukit/ChangeLog b/cpukit/ChangeLog
index 6803606eea..31cd140685 100644
--- a/cpukit/ChangeLog
+++ b/cpukit/ChangeLog
@@ -1,3 +1,10 @@
+2011-12-03	Ralf Corsépius <ralf.corsepius@rtems.org>
+
+	* libcsupport/src/getgid.c: Include <unistd.h>.
+	* libcsupport/src/setgid.c: Include <unistd.h>.
+	* libcsupport/src/getpgrp.c: Include <unistd.h>.
+	Remove unnecessary includes.
+
 2011-12-03	Ralf Corsépius <ralf.corsepius@rtems.org>
 
 	* posix/src/pthread.c (_POSIX_Threads_Default_attributes): Add
diff --git a/cpukit/libcsupport/src/getgid.c b/cpukit/libcsupport/src/getgid.c
index 7074e765e5..0a2d7602e5 100644
--- a/cpukit/libcsupport/src/getgid.c
+++ b/cpukit/libcsupport/src/getgid.c
@@ -6,6 +6,7 @@
 #include "config.h"
 #endif
 
+#include <unistd.h>
 #include <rtems/userenv.h>
 
 /*
diff --git a/cpukit/libcsupport/src/getpgrp.c b/cpukit/libcsupport/src/getpgrp.c
index 59451a32a8..459869d549 100644
--- a/cpukit/libcsupport/src/getpgrp.c
+++ b/cpukit/libcsupport/src/getpgrp.c
@@ -6,14 +6,8 @@
 #include "config.h"
 #endif
 
-#include <limits.h>
-#include <errno.h>
-#include <string.h>
-#include <sys/types.h>
-
-#include <rtems/system.h>
+#include <unistd.h>
 #include <rtems/score/object.h>
-#include <rtems/seterr.h>
 
 /*
  *  4.3.1 Get Process Group IDs, P1003.1b-1993, p. 89
diff --git a/cpukit/libcsupport/src/setgid.c b/cpukit/libcsupport/src/setgid.c
index 908899cf72..3bb51bf1ac 100644
--- a/cpukit/libcsupport/src/setgid.c
+++ b/cpukit/libcsupport/src/setgid.c
@@ -6,6 +6,7 @@
 #include "config.h"
 #endif
 
+#include <unistd.h>
 #include <rtems/userenv.h>
 
 /*