diff --git a/build-in/exit/ft_exit_utils.c b/build-in/exit/ft_exit_utils.c
index d1c3a7b..dbd697b 100644
--- a/build-in/exit/ft_exit_utils.c
+++ b/build-in/exit/ft_exit_utils.c
@@ -6,7 +6,7 @@
 /*   By: yuocak <yuocak@student.42kocaeli.com.tr>   +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2025/08/03 14:30:31 by yuocak            #+#    #+#             */
-/*   Updated: 2025/08/05 12:37:09 by yuocak           ###   ########.fr       */
+/*   Updated: 2025/08/05 14:24:51 by yuocak           ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -40,8 +40,7 @@ int	is_numeric(char *str)
 
 	i = 0;
 	sign = 1;
-	while (str[i] && (str[i] == ' ' || str[i] == '\t' || str[i] == '\n' || 
-		str[i] == '\r' || str[i] == '\f' || str[i] == '\v'))
+	while (str[i] && ft_isspace(str[i]))
 		i++;
 	if (str[i] == '-' || str[i] == '+')
 	{
diff --git a/execute/execute_external.c b/execute/execute_external.c
index dc43a6b..2e7ad43 100644
--- a/execute/execute_external.c
+++ b/execute/execute_external.c
@@ -6,11 +6,12 @@
 /*   By: yuocak <yuocak@student.42kocaeli.com.tr>   +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2025/07/07 07:45:00 by yuocak            #+#    #+#             */
-/*   Updated: 2025/08/04 10:36:42 by yuocak           ###   ########.fr       */
+/*   Updated: 2025/08/05 15:24:48 by yuocak           ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
 #include "../minishell.h"
+#include <sys/stat.h>
 
 static void	cleanup_execution(t_exec_params *params)
 {
@@ -24,8 +25,15 @@ static void	cleanup_execution(t_exec_params *params)
 
 static void	child_process(t_exec_params *params)
 {
+	struct stat	st;
+
 	setup_child_signals();
 	execve(params->command_path, params->argv, params->envp);
+	if (stat(params->command_path, &st) == 0 && S_ISDIR(st.st_mode))
+	{
+		printf("minishell: %s: Is a directory\n", params->command_path);
+		exit(126);
+	}
 	perror("minishell");
 	exit(126);
 }
diff --git a/execute/execute_multiple_utils2.c b/execute/execute_multiple_utils2.c
index ccf893c..ad3a160 100644
--- a/execute/execute_multiple_utils2.c
+++ b/execute/execute_multiple_utils2.c
@@ -6,13 +6,14 @@
 /*   By: yuocak <yuocak@student.42kocaeli.com.tr>   +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2025/07/24 13:00:00 by yuocak            #+#    #+#             */
-/*   Updated: 2025/08/05 13:23:17 by yuocak           ###   ########.fr       */
+/*   Updated: 2025/08/05 14:20:34 by yuocak           ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
 #include "../minishell.h"
 
-static void	assign_new_command(t_token **current, t_token **commands, int *cmd_index)
+static void	assign_new_command(t_token **current, t_token **commands,
+	int *cmd_index)
 {
 	t_token	*temp;
 
@@ -23,7 +24,6 @@ static void	assign_new_command(t_token **current, t_token **commands, int *cmd_i
 	*current = temp;
 }
 
-
 t_token	**split_commands(t_token *token, int cmd_count)
 {
 	t_token	**commands;