diff --git a/gaboshlib/g_calc.sh b/gaboshlib/g_calc.sh
index a8775fe..1862160 100644
--- a/gaboshlib/g_calc.sh
+++ b/gaboshlib/g_calc.sh
@@ -25,12 +25,19 @@ function g_calc {
   # do bc
   echo "scale=8; $@" >&3
   local g_bc_out
-  read g_bc_out <&4
+  if ! read -t 0 g_bc_out <&4
+  then
+    g_traceback
+    return 1
+  fi
 
   # do sed
   echo ${g_bc_out} >&5
   local g_sed_out
-  read g_sed_out <&6
+  if ! read -t 0 g_sed_out <&6
+    g_traceback
+    return 1
+  fi
 
   # echo result
   echo ${g_sed_out}