system & execute badly working

not always remove(especially when many files):

Code:

---

Callback_StartGameType()
{
system("rm -rf /root/server/scriptdata/savestata/*");
....
}

---

for couple of days:
get undefined param
+
memory size add ≈ 200

Code:

---

execute("LC_TIME=en_US date");//every 30 minute

---

C++ Linux: system() - bad work on CentOS-7-x86_64, who know is problem?