diff --git a/blocksworld/3ops/2pddl/2pddl.c b/blocksworld/3ops/2pddl/2pddl.c
index 0aae6454f..41a879828 100644
--- a/blocksworld/3ops/2pddl/2pddl.c
+++ b/blocksworld/3ops/2pddl/2pddl.c
@@ -158,7 +158,7 @@ Bool process_command_line( int argc, char *argv[] )
       if ( --argc && ++argv ) {
 	switch ( option ) {
 	case 'd':
-          gdata = ( char * ) calloc( strlen(*argv), sizeof( char ) );
+          gdata = ( char * ) calloc( strlen(*argv) + 1, sizeof( char ) );
 	  strcpy( gdata, *argv );
 	  break;
 	case 'n':
diff --git a/blocksworld/4ops/2pddl/2pddl.c b/blocksworld/4ops/2pddl/2pddl.c
index 535221908..836f28cd1 100644
--- a/blocksworld/4ops/2pddl/2pddl.c
+++ b/blocksworld/4ops/2pddl/2pddl.c
@@ -159,7 +159,7 @@ Bool process_command_line( int argc, char *argv[] )
       if ( --argc && ++argv ) {
 	switch ( option ) {
 	case 'd':
-          gdata = ( char * ) calloc( strlen(*argv), sizeof( char ) );
+          gdata = ( char * ) calloc( strlen(*argv) + 1, sizeof( char ) );
 	  strcpy( gdata, *argv );
 	  break;
 	case 'n':