diff --git a/scripts/run_test.sh b/scripts/run_test.sh
index 1a032ba..fc3505f 100755
--- a/scripts/run_test.sh
+++ b/scripts/run_test.sh
@@ -21,7 +21,7 @@ cd $TMPDIR
 
 cp ${MICROWATT_DIR}/tests/${TEST}.bin main_ram.bin
 
-${MICROWATT_DIR}/core_tb | sed 's/.*: //' | egrep '^(GPR[0-9]|LR |CTR |XER |CR [0-9])' | sort | grep -v GPR31 > test.out || true
+${MICROWATT_DIR}/core_tb | sed 's/.*: //' | grep -E '^(GPR[0-9]|LR |CTR |XER |CR [0-9])' | sort | grep -v GPR31 > test.out || true
 
 grep -v "^$" ${MICROWATT_DIR}/tests/${TEST}.out | sort | grep -v GPR31 > exp.out