diff --git a/c/src/exec/posix/src/setsid.c b/c/src/exec/posix/src/setsid.c
index 3954ae8fc7..8d56ea6e72 100644
--- a/c/src/exec/posix/src/setsid.c
+++ b/c/src/exec/posix/src/setsid.c
@@ -18,7 +18,7 @@
 
 pid_t setsid( void )
 {
-  set_errno_and_return_minus_one( ENOSYS );
+  set_errno_and_return_minus_one( EPERM );
 }
 
 
diff --git a/cpukit/posix/src/setsid.c b/cpukit/posix/src/setsid.c
index 3954ae8fc7..8d56ea6e72 100644
--- a/cpukit/posix/src/setsid.c
+++ b/cpukit/posix/src/setsid.c
@@ -18,7 +18,7 @@
 
 pid_t setsid( void )
 {
-  set_errno_and_return_minus_one( ENOSYS );
+  set_errno_and_return_minus_one( EPERM );
 }