diff --git a/exam1/compile_all.sh b/exam1/compile_all.sh
index 7435e73..0e462f9 100755
--- a/exam1/compile_all.sh
+++ b/exam1/compile_all.sh
@@ -90,6 +90,9 @@ fi
 echo -ne " [+] Shellcode size is "$(echo -ne $FULL_SHELLCODE|sed 's/\"//g'|wc -c)" bytes\n"
 echo $FULL_SHELLCODE
 
+if [ -z "$FULL_SHELLCODE" ]; then
+  exit 1;
+fi
 
 #
 # Generate shellcode.c
diff --git a/exam1/shell_bind_tcp.nasm b/exam1/shell_bind_tcp.nasm
index c9233a8..4de6816 100644
--- a/exam1/shell_bind_tcp.nasm
+++ b/exam1/shell_bind_tcp.nasm
@@ -10,7 +10,8 @@
 ;
 ;    You should have received a copy of the GNU General Public License
 ;    along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
+;
+;
 ; Filename: shell_bind_tcp.nasm
 ; Author: Andrey Arapov <andrey.arapov@gmail.com>
 ; 2013 March
diff --git a/exam1/shell_bind_tcp_smaller.nasm b/exam1/shell_bind_tcp_smaller.nasm
index 4a4b73e..25cfd43 100644
--- a/exam1/shell_bind_tcp_smaller.nasm
+++ b/exam1/shell_bind_tcp_smaller.nasm
@@ -10,7 +10,8 @@
 ;
 ;    You should have received a copy of the GNU General Public License
 ;    along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
+;
+;
 ; Filename: shell_bind_tcp_smaller.nasm
 ; Author: Andrey Arapov <andrey.arapov@gmail.com>
 ; 2013 March
diff --git a/exam2/compile_all.sh b/exam2/compile_all.sh
index d811f43..8d39875 100755
--- a/exam2/compile_all.sh
+++ b/exam2/compile_all.sh
@@ -127,6 +127,9 @@ fi
 echo -ne " [+] Shellcode size is "$(echo -ne $FULL_SHELLCODE|sed 's/\"//g'|wc -c)" bytes\n"
 echo $FULL_SHELLCODE
 
+if [ -z "$FULL_SHELLCODE" ]; then
+  exit 1;
+fi
 
 #
 # Generate shellcode.c
diff --git a/exam2/shell_reverse_tcp.nasm b/exam2/shell_reverse_tcp.nasm
index d1f006c..962d433 100644
--- a/exam2/shell_reverse_tcp.nasm
+++ b/exam2/shell_reverse_tcp.nasm
@@ -10,7 +10,8 @@
 ;
 ;    You should have received a copy of the GNU General Public License
 ;    along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
+;
+;
 ; Filename: shell_reverse_tcp.nasm
 ; Author: Andrey Arapov <andrey.arapov@gmail.com>
 ; 2013 March