diff --git a/src/builtin-exec/builtin.c b/src/builtin-exec/builtin.c
index 4a9a772..c877eea 100644
--- a/src/builtin-exec/builtin.c
+++ b/src/builtin-exec/builtin.c
@@ -55,7 +55,7 @@ int where(char** args, lst** env)
   return 0;
 }
 
-int builtin_execute(cmd* input, data_t *data, int fd_in, int fd_out)
+int builtin_execute(cmd_t* input, data_t *data, int fd_in, int fd_out)
 {
   if (strcmp(input->executable, "cd") == 0)
   {
diff --git a/src/builtin-exec/builtin.h b/src/builtin-exec/builtin.h
index bd8f3a2..b0235d3 100644
--- a/src/builtin-exec/builtin.h
+++ b/src/builtin-exec/builtin.h
@@ -12,7 +12,7 @@
 #include "../../lib/bozolib/bozolib.h"
 
 char* builtin_path(const char* executable);
-int builtin_execute(cmd* input, data_t* data, int fd_in, int fd_out);
+int builtin_execute(cmd_t* input, data_t* data, int fd_in, int fd_out);
 
 int builtin_alias(int fd_in, int fd_out, lst** aliases, char** args);
 int change_directory(char** args, lst** env);
diff --git a/src/cmd/cmd.c b/src/cmd/cmd.c
index a1c3e33..b450bf1 100644
--- a/src/cmd/cmd.c
+++ b/src/cmd/cmd.c
@@ -2,9 +2,36 @@
 
 void cmd_del(void *ptr)
 {
-	cmd* content = ptr;
+	cmd_t* content = ptr;
 
 	tab_free((void**)content->args);
 	free(content->executable);
 	free(content);
 }
+
+int cmd_init(cmd_t* command)
+{
+	command->pid = -1;
+	command->input[0] = -1;
+	command->input[1] = -1;
+	command->output[0] = -1;
+	command->output[1] = -1;
+	return 0;
+}
+
+void cmd_close(void* ptr)
+{
+	cmd_t* content = ptr;
+	if (content->input[0] > 2)
+		close(content->input[0]);
+	content->input[0] = -1;
+	if (content->input[1] > 2)
+		close(content->input[1]);
+	content->input[1] = -1;
+	if (content->output[0] > 2)
+		close(content->output[0]);
+	content->output[0] = -1;
+	if (content->output[1] > 2)
+		close(content->output[1]);
+	content->output[1] = -1;
+}
diff --git a/src/cmd/cmd.h b/src/cmd/cmd.h
index c490714..2a04704 100644
--- a/src/cmd/cmd.h
+++ b/src/cmd/cmd.h
@@ -2,6 +2,7 @@
 
 #include <stdlib.h>
 #include <stddef.h>
+#include <unistd.h>
 
 #include "../../lib/bozolib/bozolib.h"
 
@@ -9,11 +10,11 @@ typedef struct s_cmd
 {
 	char *executable;
 	char **args;
-	int fd_in;
-	int fd_out;
-  int pid;
-} cmd;
+	int input[2];
+	int output[2];
+	int pid;
+} cmd_t;
 
 void cmd_del(void* ptr);
-
-lst** cmds_init(size_t len);
+int cmd_init(cmd_t* command);
+void cmd_close(void* ptr);
diff --git a/src/cmd/cmds.c b/src/cmd/cmds.c
deleted file mode 100644
index 46092b5..0000000
--- a/src/cmd/cmds.c
+++ /dev/null
@@ -1,34 +0,0 @@
-#include "./cmd.h"
-#include <stddef.h>
-#include <stdlib.h>
-
-lst** cmds_init(size_t len)
-{
-	lst** root;
-	lst* current;
-	cmd* content;
-
-	root = calloc(sizeof(lst*), 1);
-	if (root == NULL)
-		return (NULL);
-	for (size_t i = 0; i < len; i++)
-	{
-		current = malloc(sizeof(lst));
-		if (current == NULL)
-		{
-			lst_clear(root, &free);
-			free(root);
-			return (NULL);
-		}
-		lst_addback(root, current);
-		content = calloc(sizeof(cmd), 1);
-		if (content == NULL)
-		{
-			lst_clear(root, &free);
-			free(root);
-			return (NULL);
-		}
-		current->content = content;
-	}
-	return (root);
-}
diff --git a/src/exec/exec.c b/src/exec/exec.c
index ae09f17..3b28386 100644
--- a/src/exec/exec.c
+++ b/src/exec/exec.c
@@ -11,36 +11,36 @@
 #include "../builtin-exec/builtin.h"
 #include "../data/data.h"
 
-int execute(cmd* input, lst** env)
+int execute(lst** cmds, cmd_t* cmd, lst** env)
 {
   int pid;
-  int exitcode;
-  if (input->executable != NULL)
+  if (cmd->executable != NULL)
     pid = fork();
   else
   {
     dprintf(2, "Executable inconnu\n");
     return 1;
   }
-  if (pid == 0)
+  if (pid == -1)
+	  return 1;
+  else if (pid == 0)
   {
-    dup2(input->fd_out, 1);
-    dup2(input->fd_in, 0);
-    if (input->fd_in > 2)
-      close(input->fd_in);
-    if (input->fd_out > 2)
-      close(input->fd_out);
-    exitcode = execve(input->executable, input->args, get_env_str(env));
+	char** env_str = get_env_str(env);
+	if (env_str == NULL)
+		return 1;
+	dup2(cmd->output[0], 1);
+	dup2(cmd->input[0], 0);
+	lst_iter(cmds, &cmd_close);
+  	execve(cmd->executable, cmd->args, env_str);
+	dprintf(2, "execve failed\n");
+	free((void**)env_str);
+	return 1;
   }
   else
   {
-    if (input->fd_in > 2)
-      close(input->fd_in);
-    if (input->fd_out > 2)
-      close(input->fd_out);
-    waitpid(pid, &exitcode, 0);
+	cmd->pid = pid;
   }
-  return exitcode;
+  return 0;
 }
 
 char* get_executable_path(const char* executable, lst** env)
@@ -72,27 +72,42 @@ char* get_executable_path(const char* executable, lst** env)
   return NULL;
 }
 
+void add_fd(int fds[2], int fd)
+{
+	if (fds[0] == -1)
+		fds[0] = fd;
+	else
+		fds[1] = fd;
+}
+
 int cmds_list_exec(lst** cmds, data_t *data)
 {
 	lst* current = *cmds;
-	cmd* content;
+	cmd_t* content;
 	int fds[2];
 	while (current != NULL)
 	{
 		content = current->content;
-		if (pipe(fds) < 0)
-			return 1;
 		if (current->next != NULL)
 		{
-			content->fd_out = fds[1];
-			((cmd*)current->next->content)->fd_in = fds[0];
+			if (pipe(fds) == -1)
+				return 1;
+			add_fd(content->output, fds[1]);
+			add_fd(((cmd_t*)current->next->content)->input, fds[0]);
 		}
 		if (content->args[0] == NULL)
 			;
 		else if (content->executable == NULL)
 			dprintf(2, "zzsh: command not found: %s\n", content->args[0]);
 		else if (builtin_execute(content, data, fds[0], fds[1]) == 1)
-			execute(content, data->env);
+		{
+			if (execute(cmds, content, data->env))
+			{
+				cmd_close(content);
+				return 1;
+			}
+			cmd_close(content);
+		}
 		current = current->next;
 	}
 	return 0;
diff --git a/src/exec/exec.h b/src/exec/exec.h
index 7ee12df..6f946ed 100644
--- a/src/exec/exec.h
+++ b/src/exec/exec.h
@@ -5,6 +5,4 @@
 #include "../data/data.h"
 
 int cmds_list_exec(lst** cmds, data_t *data);
-int execute(cmd* input, lst** env);
-int builtin_execute(cmd* input, data_t* data, int fd_int, int fd_out);
 char* get_executable_path(const char* executable, lst** env);
diff --git a/src/main.c b/src/main.c
index cd72bf8..006740d 100644
--- a/src/main.c
+++ b/src/main.c
@@ -51,7 +51,7 @@ int main(int ac, char **av, char **env_str)
 		}
 		line = get_user_input(&data);
 	}
-	lst_clear(data.aliases, alias_del);
+	lst_clear(data.aliases, &alias_del);
 	lst_clear(data.env, &env_del);
 	return (0);
  
diff --git a/src/parsing/parsing.c b/src/parsing/parsing.c
index 1dc2483..991b422 100644
--- a/src/parsing/parsing.c
+++ b/src/parsing/parsing.c
@@ -9,9 +9,11 @@ char* parsing_executable(const char* executable, data_t *data)
 	return (get_executable_path(executable, data->env));
 }
 
-int parsing_cmd(char *str, cmd* command, data_t *data)
+int parsing_cmd(char *str, cmd_t* command, data_t *data)
 {
 	char* tmp;
+	if (cmd_init(command))
+		return 1;
 	if (get_redirections(str, command))
 		return 1;
 	command->args = split_quoted_charset(str, "\t ");
@@ -52,20 +54,56 @@ lst **parsing_pipe(const char *str, data_t *data)
 	cmds_str = split_quoted_charset(str, "|");
 	if (cmds_str == NULL)
 		return (NULL);
-	cmds = cmds_init(tablen((const void**)cmds_str));
+	cmds = malloc(sizeof(lst*));
 	if (cmds == NULL)
 	{
 		tab_free((void**)cmds_str);
 		return (NULL);
 	}
-	current = *cmds;
+	if (cmds_str[0] != NULL)
+	{
+		*cmds = malloc(sizeof(lst));
+		if (*cmds == NULL)
+		{
+			free(cmds);
+			tab_free((void**)cmds_str);
+			return (NULL);
+		}
+		current = *cmds;
+	}
 	for (size_t i = 0; cmds_str[i] != NULL; i++)
 	{
+		current->content = malloc(sizeof(cmd_t));
+		if (current->content == NULL)
+		{
+			tab_free((void**)cmds_str);
+			lst_clear(cmds, &cmd_del);
+			return NULL;
+		}
 		if (parsing_cmd(cmds_str[i], current->content, data))
 		{
 			tab_free((void**)cmds_str);
+			lst_clear(cmds, &cmd_del);
 			return NULL;
 		}
+		if (cmds_str[i + 1] != NULL)
+		{
+			current->next = malloc(sizeof(lst));
+			if (current->next == NULL)
+			{
+				tab_free((void**)cmds_str);
+				lst_clear(cmds, &cmd_del);
+				return NULL;
+			}
+		}
+		else
+			current->next = NULL;
+		if (i == 0)
+			if (((cmd_t*) current->content)->input[0] == -1)
+				((cmd_t*) current->content)->input[0] = 0;
+		if (current->next == NULL)
+			if (((cmd_t*) current->content)->output[0] == -1)
+				((cmd_t*) current->content)->output[0] = 1;
 		current = current->next;
 	}
 	tab_free((void**)cmds_str);
diff --git a/src/redirection/redirection.c b/src/redirection/redirection.c
index 889a05c..b9d686f 100644
--- a/src/redirection/redirection.c
+++ b/src/redirection/redirection.c
@@ -36,32 +36,35 @@ static size_t get_path_size(const char* str)
 	return i;
 }
 
-int redirection_fill(const char* str, size_t nb_symbols, cmd* command, const char *path)
+int redirection_fill(const char* str, size_t nb_symbols, cmd_t* command, const char *path)
 {
-	int problem = 0;
+	int fd;
 	if (str[0] == '>')
 	{
-		if (command->fd_out > 2)
-			close(command->fd_out);
 		if (nb_symbols == 1)
-			command->fd_out = open(path, O_TRUNC | O_CREAT | O_WRONLY, 0644);
+			fd = open(path, O_TRUNC | O_CREAT | O_WRONLY, 0644);
 		else
-			command->fd_out = open(path, O_APPEND | O_CREAT | O_WRONLY, 0644);
-		problem = command->fd_out == -1;
+			fd = open(path, O_APPEND | O_CREAT | O_WRONLY, 0644);
+		if (fd == -1)
+			dprintf(2, "zzsh: \"%s\": file error\n", path);
+		if (command->output[0] > 2)
+			close(command->output[0]);
+		command->output[0] = fd;
+		return (fd == -1);
 	}
 	else
 	{
-		if (command->fd_in > 2)
-			close(command->fd_in);
 		if (nb_symbols == 1)
-			command->fd_in = open(path, O_RDONLY);
+			fd = open(path, O_RDONLY);
 		else
-			command->fd_in = open(path, O_RDONLY);
-		problem = command->fd_in == -1;
+			fd = open(path, O_RDONLY);
+		if (fd == -1)
+			dprintf(2, "zzsh: \"%s\": file error\n", path);
+		if (command->input[0] > 2)
+			close(command->input[0]);
+		command->input[0] = fd;
+		return (fd == -1);
 	}
-	if (problem)
-		dprintf(2, "zzsh: \"%s\": file error\n", path);
-	return problem;
 }
 
 static size_t get_concecutive(const char *str)
@@ -71,7 +74,7 @@ static size_t get_concecutive(const char *str)
 	return (i);
 }
 
-int get_redirections(char *str, cmd* command)
+int get_redirections(char *str, cmd_t* command)
 {
 	char *redirection;
 	char redirection_symbol[3] = "<>";
diff --git a/src/redirection/redirection.h b/src/redirection/redirection.h
index a559dd8..581e560 100644
--- a/src/redirection/redirection.h
+++ b/src/redirection/redirection.h
@@ -8,4 +8,4 @@
 #include "../cmd/cmd.h"
 #include "../utils/utils.h"
 
-int get_redirections(char *str, cmd* command);
+int get_redirections(char *str, cmd_t* command);