diff --git a/testcases/open_posix_testsuite/conformance/interfaces/sem_open/1-1.c b/testcases/open_posix_testsuite/conformance/interfaces/sem_open/1-1.c
index b77b23f..a083244 100644
--- a/testcases/open_posix_testsuite/conformance/interfaces/sem_open/1-1.c
+++ b/testcases/open_posix_testsuite/conformance/interfaces/sem_open/1-1.c
@@ -22,7 +22,6 @@
 
 #define TEST "1-1"
 #define FUNCTION "sem_open"
-#define ERROR_PREFIX "unexpected error: " FUNCTION " " TEST ": "
 
 int main(void)
 {
diff --git a/testcases/open_posix_testsuite/conformance/interfaces/sem_open/1-2.c b/testcases/open_posix_testsuite/conformance/interfaces/sem_open/1-2.c
index c8b9297..23240b2 100644
--- a/testcases/open_posix_testsuite/conformance/interfaces/sem_open/1-2.c
+++ b/testcases/open_posix_testsuite/conformance/interfaces/sem_open/1-2.c
@@ -22,7 +22,6 @@
 
 #define TEST "1-2"
 #define FUNCTION "sem_open"
-#define ERROR_PREFIX "unexpected error: " FUNCTION " " TEST ": "
 
 int main(void)
 {
diff --git a/testcases/open_posix_testsuite/conformance/interfaces/sem_open/4-1.c b/testcases/open_posix_testsuite/conformance/interfaces/sem_open/4-1.c
index a190efc..d10c295 100644
--- a/testcases/open_posix_testsuite/conformance/interfaces/sem_open/4-1.c
+++ b/testcases/open_posix_testsuite/conformance/interfaces/sem_open/4-1.c
@@ -23,7 +23,6 @@
 
 #define TEST "4-1"
 #define FUNCTION "sem_open"
-#define ERROR_PREFIX "unexpected error: " FUNCTION " " TEST ": "
 
 int main(void)
 {
diff --git a/testcases/open_posix_testsuite/conformance/interfaces/sem_open/5-1.c b/testcases/open_posix_testsuite/conformance/interfaces/sem_open/5-1.c
index e316056..56c8a93 100644
--- a/testcases/open_posix_testsuite/conformance/interfaces/sem_open/5-1.c
+++ b/testcases/open_posix_testsuite/conformance/interfaces/sem_open/5-1.c
@@ -22,7 +22,6 @@
 
 #define TEST "5-1"
 #define FUNCTION "sem_open"
-#define ERROR_PREFIX "unexpected error: " FUNCTION " " TEST ": "
 
 int main(void)
 {
diff --git a/testcases/open_posix_testsuite/conformance/interfaces/sem_open/6-1.c b/testcases/open_posix_testsuite/conformance/interfaces/sem_open/6-1.c
index 25eab96..f057656 100644
--- a/testcases/open_posix_testsuite/conformance/interfaces/sem_open/6-1.c
+++ b/testcases/open_posix_testsuite/conformance/interfaces/sem_open/6-1.c
@@ -20,7 +20,6 @@
 
 #define TEST "6-1"
 #define FUNCTION "sem_open"
-#define ERROR_PREFIX "unexpected error: " FUNCTION " " TEST ": "
 
 int main(void)
 {