diff --git a/mini_shell.c b/mini_shell.c
index d524330..c7acddd 100644
--- a/mini_shell.c
+++ b/mini_shell.c
@@ -1,9 +1,34 @@
 #include <stdio.h>
+#include <assert.h>
+#include <unistd.h>
 #include <string.h>
 #include <stdlib.h>
 
+void lire(char **, char **, char **);
+char * lireChaine3();
+void changeDirectory(char * path);
+int subString (const char *chaine, int debut, int fin, char *result);
+void erreur(char *s);
+
 int main(int argc, char **argv)
 {
+	char **arg1, **arg2, **arg3;
+	lire(arg1, arg2, arg3);
+
+	if(strcmp(*arg1, "cd") == 0)
+	{
+		// On change de répertoire
+		changeDirectory(*arg2);
+	}
+	
+
+}
+void changeDirectory(char * path)
+{
+	if(strcmp(path, "") == 0)
+		chdir(getenv("HOME"));
+	else if(chdir(path) != 0 )
+		erreur("Impossible de changer de répertoire");
 }
 void lire(char** arg1, char** arg2, char** arg3) 
 {
@@ -15,3 +40,53 @@ void lire(char** arg1, char** arg2, char** arg3)
 	*arg2 = strtok((char *)0," ");
 	*arg3 = strtok((char *)0," ");
 }
+char *lireChaine3() 
+{
+	char *ptr, *ptr1;
+	int c;
+	int i=0;
+	int nb=10;
+
+	ptr=malloc(nb);
+	assert(ptr);
+
+	while((c=getchar()) !=  '\n' && c != EOF) 
+	{
+		if (i==nb-1) 
+		{
+			ptr1=malloc(nb=nb*2);
+			assert(ptr1);
+			ptr[i]='\0';
+			strcpy(ptr1,ptr);
+			free(ptr);
+			ptr=ptr1;
+		}
+		ptr[i]=c;
+		i++;
+    }
+    ptr[i]='\0';
+
+    if(c == EOF && i == 0) 
+        ptr = NULL; 
+    else
+		if (i+1 != nb) 
+		{
+			ptr1=malloc(i+1);
+			assert(ptr1);
+			strcpy(ptr1,ptr);
+			free(ptr);
+			ptr=ptr1;
+        }
+    return ptr;
+}
+void erreur(char *s)
+{
+	perror(s);
+	exit(-2);
+}
+int subString (const char *chaine, int debut, int fin, char *result)
+{
+	result[fin+1-debut] = '\0';
+	memcpy (result, (char *)chaine+debut, fin+1-debut);
+	return (fin+1-debut);
+}