diff --git a/core/client.c b/core/client.c
index 1227cd6..46cefc4 100644
--- a/core/client.c
+++ b/core/client.c
@@ -17,20 +17,20 @@ struct ipc_client * ipc_server_client_copy (const struct ipc_client *p)
     return copy;
 }
 
-int ipc_server_client_eq (const struct ipc_client *p1, const struct ipc_client *p2)
+int32_t ipc_server_client_eq (const struct ipc_client *p1, const struct ipc_client *p2)
 {
     return (p1->version == p2->version && p1->index == p2->index
             && p1->proc_fd == p2->proc_fd);
 }
 
 void ipc_server_client_gen (struct ipc_client *p
-        , unsigned int index, unsigned int version)
+        , uint32_t index, uint32_t version)
 {
     p->version = version;
     p->index = index;
 }
 
-int ipc_client_add (struct ipc_clients *clients, struct ipc_client *p)
+int32_t ipc_clients_add (struct ipc_clients *clients, struct ipc_client *p)
 {
     assert(clients != NULL);
     assert(p != NULL);
@@ -47,7 +47,7 @@ int ipc_client_add (struct ipc_clients *clients, struct ipc_client *p)
     return 0;
 }
 
-int ipc_client_del (struct ipc_clients *clients, struct ipc_client *p)
+int32_t ipc_clients_del (struct ipc_clients *clients, struct ipc_client *p)
 {
     assert(clients != NULL);
     assert(p != NULL);
@@ -56,10 +56,9 @@ int ipc_client_del (struct ipc_clients *clients, struct ipc_client *p)
         return -1;
     }
 
-    int i;
+    int32_t i;
     for (i = 0; i < clients->size; i++) {
         if (clients->clients[i] == p) {
-
             clients->clients[i] = clients->clients[clients->size-1];
             clients->size--;
             if (clients->size == 0) {
@@ -90,7 +89,7 @@ void client_print (struct ipc_client *p)
 
 void ipc_clients_print (struct ipc_clients *ap)
 {
-    int i;
+    int32_t i;
     for (i = 0; i < ap->size; i++) {
         printf("%d : ", i);
         client_print(ap->clients[i]);
diff --git a/core/client.h b/core/client.h
index 08d663c..8366fe0 100644
--- a/core/client.h
+++ b/core/client.h
@@ -1,29 +1,10 @@
 #ifndef __IPC_CLIENT_H__
 #define __IPC_CLIENT_H__
 
-struct ipc_client {
-    unsigned int version;
-    unsigned int index;
-    int proc_fd;
-};
-
-struct ipc_clients {
-	struct ipc_client **clients;
-	int size;
-};
-
-// store and remove only pointers on allocated structures
-int ipc_client_add (struct ipc_clients *, struct ipc_client *);
-int ipc_client_del (struct ipc_clients *, struct ipc_client *);
+#include <stdint.h>
+#include "ipc.h"
 
 void ipc_clients_print (struct ipc_clients *);
-void ipc_clients_free  (struct ipc_clients *);
-
-struct ipc_client * ipc_server_client_copy (const struct ipc_client *p);
-int ipc_server_client_eq (const struct ipc_client *p1, const struct ipc_client *p2);
-// create the service client structure
-void ipc_server_client_gen (struct ipc_client *p
-        , unsigned int index, unsigned int version);
-
 void client_print (struct ipc_client *);
+
 #endif
diff --git a/core/communication.c b/core/communication.c
index 981fcb4..f56447a 100644
--- a/core/communication.c
+++ b/core/communication.c
@@ -8,7 +8,7 @@
 #include <stdio.h>
 #include <errno.h>
 
-void service_path (char *path, const char *sname, int index, int version)
+void service_path (char *path, const char *sname, int32_t index, int32_t version)
 {
     assert (path != NULL);
     assert (sname != NULL);
@@ -16,7 +16,7 @@ void service_path (char *path, const char *sname, int index, int version)
     snprintf (path, PATH_MAX, "%s/%s-%d-%d", RUNDIR, sname, index, version);
 }
 
-int ipc_server_init (char **env
+int32_t ipc_server_init (char **env
         , struct ipc_service *srv, const char *sname)
 {
     if (srv == NULL)
@@ -33,7 +33,7 @@ int ipc_server_init (char **env
     // gets the service path
     service_path (srv->spath, sname, srv->index, srv->version);
 
-    int ret = usock_init (&srv->service_fd, srv->spath);
+    int32_t ret = usock_init (&srv->service_fd, srv->spath);
 	if (ret < 0) {
 		handle_err ("ipc_server_init", "usock_init ret < 0");
 		return -1;
@@ -42,12 +42,12 @@ int ipc_server_init (char **env
 	return 0;
 }
 
-int ipc_server_accept (struct ipc_service *srv, struct ipc_client *p)
+int32_t ipc_server_accept (struct ipc_service *srv, struct ipc_client *p)
 {
     assert (srv != NULL);
     assert (p != NULL);
 
-    int ret = usock_accept (srv->service_fd, &p->proc_fd);
+    int32_t ret = usock_accept (srv->service_fd, &p->proc_fd);
 	if (ret < 0) {
 		handle_err ("ipc_server_accept", "usock_accept < 0");
 		return -1;
@@ -57,30 +57,30 @@ int ipc_server_accept (struct ipc_service *srv, struct ipc_client *p)
 }
 
 // empty the srv structure
-int ipc_server_close (struct ipc_service *srv)
+int32_t ipc_server_close (struct ipc_service *srv)
 {
     usock_close (srv->service_fd);
-	int ret = usock_remove (srv->spath);
+	int32_t ret = usock_remove (srv->spath);
 	ipc_service_empty (srv);
     return ret;
 }
 
-int ipc_server_close_client (struct ipc_client *p)
+int32_t ipc_server_close_client (struct ipc_client *p)
 {
     return usock_close (p->proc_fd);
 }
 
-int ipc_server_read (const struct ipc_client *p, struct ipc_message *m)
+int32_t ipc_server_read (const struct ipc_client *p, struct ipc_message *m)
 {
     return ipc_message_read (p->proc_fd, m);
 }
 
-int ipc_server_write (const struct ipc_client *p, const struct ipc_message *m)
+int32_t ipc_server_write (const struct ipc_client *p, const struct ipc_message *m)
 {
     return ipc_message_write (p->proc_fd, m);
 }
 
-int ipc_application_connection (char **env
+int32_t ipc_application_connection (char **env
         , struct ipc_service *srv, const char *sname)
 {
     // TODO
@@ -101,7 +101,7 @@ int ipc_application_connection (char **env
     // gets the service path
     service_path (srv->spath, sname, srv->index, srv->version);
 
-    int ret = usock_connect (&srv->service_fd, srv->spath);
+    int32_t ret = usock_connect (&srv->service_fd, srv->spath);
 	if (ret < 0) {
 		handle_err ("ipc_application_connection", "usock_connect ret <= 0");
 		return -1;
@@ -111,27 +111,27 @@ int ipc_application_connection (char **env
 }
 
 // close the socket
-int ipc_application_close (struct ipc_service *srv)
+int32_t ipc_application_close (struct ipc_service *srv)
 {
     return usock_close (srv->service_fd);
 }
 
-int ipc_application_read (struct ipc_service *srv, struct ipc_message *m)
+int32_t ipc_application_read (struct ipc_service *srv, struct ipc_message *m)
 {   
     return ipc_message_read (srv->service_fd, m);
 }
 
-int ipc_application_write (struct ipc_service *srv, const struct ipc_message *m)
+int32_t ipc_application_write (struct ipc_service *srv, const struct ipc_message *m)
 {
     return ipc_message_write (srv->service_fd, m);
 }
 
 
 /*calculer le max filedescriptor*/
-static int get_max_fd_from_ipc_clients_ (struct ipc_clients *clients)
+static int32_t get_max_fd_from_ipc_clients_ (struct ipc_clients *clients)
 {
-    int i;
-    int max = 0;
+    int32_t i;
+    int32_t max = 0;
 
     for (i = 0; i < clients->size; i++ ) {
         if (clients->clients[i]->proc_fd > max) {
@@ -142,10 +142,10 @@ static int get_max_fd_from_ipc_clients_ (struct ipc_clients *clients)
     return max;
 }
 
-static int get_max_fd_from_ipc_services_ (struct ipc_services *services)
+static int32_t get_max_fd_from_ipc_services_ (struct ipc_services *services)
 {
-    int i;
-    int max = 0;
+    int32_t i;
+    int32_t max = 0;
 
     for (i = 0; i < services->size; i++ ) {
         if (services->services[i]->service_fd > max) {
@@ -166,8 +166,8 @@ static int get_max_fd_from_ipc_services_ (struct ipc_services *services)
  * -1 = error
  */
 
-int ipc_server_select (struct ipc_clients *clients, struct ipc_service *srv
-        , struct ipc_clients *active_clients, int *new_connection)
+int32_t ipc_server_select (struct ipc_clients *clients, struct ipc_service *srv
+        , struct ipc_clients *active_clients, int32_t *new_connection)
 {
 	*new_connection = 0;
     assert (clients != NULL);
@@ -176,15 +176,15 @@ int ipc_server_select (struct ipc_clients *clients, struct ipc_service *srv
     // delete previous read active_clients array
     ipc_clients_free (active_clients);
 
-    int i, j;
+    int32_t i, j;
     /* master file descriptor list */
     fd_set master;
     fd_set readf;
 
     /* maximum file descriptor number */
-    int fdmax;
+    int32_t fdmax;
     /* listening socket descriptor */
-    int listener = srv->service_fd;
+    int32_t listener = srv->service_fd;
 
     /* clear the master and temp sets */
     FD_ZERO(&master);
@@ -212,7 +212,7 @@ int ipc_server_select (struct ipc_clients *clients, struct ipc_service *srv
 			} else {
 				for(j = 0; j < clients->size; j++) {
 					if(i == clients->clients[j]->proc_fd ) {
-						ipc_client_add (active_clients, clients->clients[j]);
+						ipc_clients_add (active_clients, clients->clients[j]);
 					}
 				}
 			}
@@ -232,7 +232,7 @@ int ipc_server_select (struct ipc_clients *clients, struct ipc_service *srv
  * -1 = error
  */
 
-int ipc_application_select (struct ipc_services *services, struct ipc_services *active_services)
+int32_t ipc_application_select (struct ipc_services *services, struct ipc_services *active_services)
 {
     assert (services != NULL);
     assert (active_services != NULL);
@@ -240,13 +240,13 @@ int ipc_application_select (struct ipc_services *services, struct ipc_services *
     // delete previous read active_services array
     ipc_services_free (active_services);
 
-    int i, j;
+    int32_t i, j;
     /* master file descriptor list */
     fd_set master;
     fd_set readf;
 
     /* maximum file descriptor number */
-    int fdmax;
+    int32_t fdmax;
 
     /* clear the master and temp sets */
     FD_ZERO(&master);
@@ -269,7 +269,7 @@ int ipc_application_select (struct ipc_services *services, struct ipc_services *
 		if (FD_ISSET(i, &readf)) {
 			for(j = 0; j < services->size; j++) {
 				if(i == services->services[j]->service_fd ) {
-					ipc_service_add (active_services, services->services[j]);
+					ipc_services_add (active_services, services->services[j]);
 				}
 			}
 		}
@@ -278,7 +278,7 @@ int ipc_application_select (struct ipc_services *services, struct ipc_services *
 	return 0;
 }
 
-int handle_new_connection (struct ipc_service *srv
+int32_t handle_new_connection (struct ipc_service *srv
 		, struct ipc_clients *clients
 		, struct ipc_client **new_client)
 {
@@ -289,33 +289,33 @@ int handle_new_connection (struct ipc_service *srv
         handle_error("server_accept < 0");
 		return 1;
     } else {
-        printf("new connection\n");
+        // printf("new connection\n");
     }
 
-    if (ipc_client_add (clients, *new_client) < 0) {
-        handle_error("ipc_client_add < 0");
+    if (ipc_clients_add (clients, *new_client) < 0) {
+        handle_error("ipc_clients_add < 0");
 		return 1;
     }
 
 	return 0;
 }
 
-int ipc_service_poll_event (struct ipc_clients *clients, struct ipc_service *srv
+int32_t ipc_service_poll_event (struct ipc_clients *clients, struct ipc_service *srv
         , struct ipc_event *event)
 {
     assert (clients != NULL);
 
 	IPC_EVENT_CLEAN(event);
 
-    int i, j;
+    int32_t i, j;
     /* master file descriptor list */
     fd_set master;
     fd_set readf;
 
     /* maximum file descriptor number */
-    int fdmax;
+    int32_t fdmax;
     /* listening socket descriptor */
-    int listener = srv->service_fd;
+    int32_t listener = srv->service_fd;
 
     /* clear the master and temp sets */
     FD_ZERO(&master);
@@ -349,7 +349,7 @@ int ipc_service_poll_event (struct ipc_clients *clients, struct ipc_service *srv
 					if(i == clients->clients[j]->proc_fd ) {
 						// listen to what they have to say (disconnection or message)
 						// then add a client to `event`, the ipc_event structure
-						int ret = 0;
+						int32_t ret = 0;
 						struct ipc_message *m = NULL;
 						m = malloc (sizeof(struct ipc_message));
 						if (m == NULL) {
@@ -374,8 +374,8 @@ int ipc_service_poll_event (struct ipc_clients *clients, struct ipc_service *srv
 							if (ipc_server_close_client (pc) < 0) {
 								handle_err( "ipc_service_poll_event", "ipc_server_close_client < 0");
 							}
-							if (ipc_client_del (clients, pc) < 0) {
-								handle_err( "ipc_service_poll_event", "ipc_client_del < 0");
+							if (ipc_clients_del (clients, pc) < 0) {
+								handle_err( "ipc_service_poll_event", "ipc_clients_del < 0");
 							}
 							ipc_message_empty (m);
 							free (m);
@@ -398,19 +398,19 @@ int ipc_service_poll_event (struct ipc_clients *clients, struct ipc_service *srv
 	return 0;
 }
 
-int ipc_application_poll_event_ (struct ipc_services *services, struct ipc_event *event, int interactive)
+int32_t ipc_application_poll_event_ (struct ipc_services *services, struct ipc_event *event, int32_t interactive)
 {
     assert (services != NULL);
 
 	IPC_EVENT_CLEAN(event);
 
-    int i, j;
+    int32_t i, j;
     /* master file descriptor list */
     fd_set master;
     fd_set readf;
 
     /* maximum file descriptor number */
-    int fdmax;
+    int32_t fdmax;
 
     /* clear the master and temp sets */
     FD_ZERO(&master);
@@ -455,7 +455,7 @@ int ipc_application_poll_event_ (struct ipc_services *services, struct ipc_event
 				if(i == services->services[j]->service_fd ) {
 					// listen to what they have to say (disconnection or message)
 					// then add a client to `event`, the ipc_event structure
-					int ret = 0;
+					int32_t ret = 0;
 					struct ipc_message *m = NULL;
 					m = malloc (sizeof(struct ipc_message));
 					if (m == NULL) {
@@ -480,8 +480,8 @@ int ipc_application_poll_event_ (struct ipc_services *services, struct ipc_event
 						if (ipc_application_close (ps) < 0) {
 							handle_err( "ipc_application_poll_event", "ipc_application_close < 0");
 						}
-						if (ipc_service_del (services, ps) < 0) {
-							handle_err( "ipc_application_poll_event", "ipc_service_del < 0");
+						if (ipc_services_del (services, ps) < 0) {
+							handle_err( "ipc_application_poll_event", "ipc_services_del < 0");
 						}
 						ipc_message_empty (m);
 						free (m);
@@ -504,10 +504,10 @@ int ipc_application_poll_event_ (struct ipc_services *services, struct ipc_event
 	return 0;
 }
 
-int ipc_application_poll_event (struct ipc_services *services, struct ipc_event *event) {
+int32_t ipc_application_poll_event (struct ipc_services *services, struct ipc_event *event) {
 	return ipc_application_poll_event_ (services, event, 0);
 }
 
-int ipc_application_peek_event (struct ipc_services *services, struct ipc_event *event) {
+int32_t ipc_application_peek_event (struct ipc_services *services, struct ipc_event *event) {
 	return ipc_application_poll_event_ (services, event, 1);
 }
diff --git a/core/communication.h b/core/communication.h
index 8488c7e..c98ee75 100644
--- a/core/communication.h
+++ b/core/communication.h
@@ -5,53 +5,16 @@
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h> // error numbers
-#include "message.h"
 
+
+#include "ipc.h"
 #include "client.h"
 #include "event.h"
-
-#define COMMUNICATION_VERSION 1
+#include "message.h"
 
 #define IPC_WITH_UNIX_SOCKETS
 #ifdef  IPC_WITH_UNIX_SOCKETS
 #include "usocket.h"
 #endif
-// SERVICE
-
-// srv->version and srv->index must be already set
-// init unix socket + fill srv->spath
-int ipc_server_init (char **env
-		, struct ipc_service *srv, const char *sname);
-int ipc_server_close (struct ipc_service *srv);
-int ipc_server_close_client (struct ipc_client *p);
-int ipc_server_accept (struct ipc_service *srv, struct ipc_client *p);
-
-// 1 on a recipient socket close
-int ipc_server_read (const struct ipc_client *, struct ipc_message *m);
-int ipc_server_write (const struct ipc_client *, const struct ipc_message *m);
-
-int ipc_server_select (struct ipc_clients * clients, struct ipc_service *srv
-        , struct ipc_clients *active_clients, int *new_connection);
-
-int ipc_service_poll_event (struct ipc_clients *clients, struct ipc_service *srv
-        , struct ipc_event *event);
-
-// APPLICATION
-
-// Initialize connection with unix socket
-// send the connection string to $TMP/<service>
-// fill srv->spath && srv->service_fd
-int ipc_application_connection (char **env
-		, struct ipc_service *, const char *);
-int ipc_application_close (struct ipc_service *);
-
-// 1 on a recipient socket close
-int ipc_application_read (struct ipc_service *srv, struct ipc_message *m);
-int ipc_application_write (struct ipc_service *, const struct ipc_message *m);
-
-int ipc_application_select (struct ipc_services *services, struct ipc_services *active_services);
-
-int ipc_application_poll_event (struct ipc_services *services, struct ipc_event *event);
-int ipc_application_peek_event (struct ipc_services *services, struct ipc_event *event);
 
 #endif
diff --git a/core/error.h b/core/error.h
index 41b2c6b..cd1c780 100644
--- a/core/error.h
+++ b/core/error.h
@@ -1,17 +1,10 @@
 #ifndef __IPC_ERROR_H__
 #define __IPC_ERROR_H__
 
-#include "logger.h"
-
-enum ipc_errors {
-	IPC_ERROR_NOT_ENOUGH_MEMORY
-	, IPC_ERROR_WRONG_PARAMETERS
-	, IPC_ERROR_READ
-};
-
 // #define IPC_WITH_ERRORS                               3
 
 #ifdef IPC_WITH_ERRORS
+#include "logger.h"
 #define handle_error(msg) \
     do { log_error (msg); exit(EXIT_FAILURE); } while (0)
 
diff --git a/core/event.h b/core/event.h
index 9ce46eb..eb97be6 100644
--- a/core/event.h
+++ b/core/event.h
@@ -1,23 +1,9 @@
 #ifndef __IPC_EVENT__
 #define __IPC_EVENT__
 
+#include "ipc.h"
 #include "message.h"
 
-enum ipc_event_type {
-	IPC_EVENT_TYPE_NOT_SET
-	, IPC_EVENT_TYPE_ERROR
-	, IPC_EVENT_TYPE_STDIN
-	, IPC_EVENT_TYPE_CONNECTION
-	, IPC_EVENT_TYPE_DISCONNECTION
-	, IPC_EVENT_TYPE_MESSAGE
-};
-
-struct ipc_event {
-	enum ipc_event_type type;
-	void* origin; // currently used as an client or service pointer
-	void* m; // message pointer
-};
-
 #define IPC_EVENT_SET(pevent,type_,message_,origin_) {\
 	pevent->type = type_; \
 	pevent->m = message_; \
diff --git a/core/ipc.h b/core/ipc.h
index 5bd680c..c073a85 100644
--- a/core/ipc.h
+++ b/core/ipc.h
@@ -1,14 +1,181 @@
 #ifndef __IPC_H__
 #define __IPC_H__
 
-#include "client.h"
-#include "communication.h"
-#include "error.h"
-#include "event.h"
-#include "logger.h"
-#include "message.h"
-#include "queue.h"
-#include "usocket.h"
-#include "utils.h"
+#include <stdint.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h> // error numbers
+#include <time.h>
+
+#define RUNDIR "/run/ipc/"
+#define PATH_MAX 4096
+#define IPC_HEADER_SIZE  5
+#define IPC_MAX_MESSAGE_SIZE  8000000-IPC_HEADER_SIZE
+// #define IPC_MAX_MESSAGE_SIZE  100-IPC_HEADER_SIZE
+// #include "queue.h"
+
+#define IPC_VERSION 1
+
+
+enum msg_types {
+	MSG_TYPE_SERVER_CLOSE = 0
+	, MSG_TYPE_ERR
+	, MSG_TYPE_DATA
+} message_types;
+
+enum ipc_event_type {
+	IPC_EVENT_TYPE_NOT_SET
+	, IPC_EVENT_TYPE_ERROR
+	, IPC_EVENT_TYPE_STDIN
+	, IPC_EVENT_TYPE_CONNECTION
+	, IPC_EVENT_TYPE_DISCONNECTION
+	, IPC_EVENT_TYPE_MESSAGE
+};
+
+enum ipc_errors {
+	IPC_ERROR_NOT_ENOUGH_MEMORY
+	, IPC_ERROR_WRONG_PARAMETERS
+	, IPC_ERROR_READ
+};
+
+struct ipc_service {
+    uint32_t version;
+    uint32_t index;
+    char spath[PATH_MAX];
+    int32_t service_fd;
+};
+
+struct ipc_services {
+	struct ipc_service ** services;
+	int32_t size;
+};
+
+struct ipc_client {
+    uint32_t version;
+    uint32_t index;
+    int32_t proc_fd;
+};
+
+struct ipc_clients {
+	struct ipc_client **clients;
+	int32_t size;
+};
+
+struct ipc_message {
+    char type;
+    uint32_t length;
+    char *payload;
+};
+
+struct ipc_event {
+	enum ipc_event_type type;
+	void* origin; // currently used as an client or service pointer
+	void* m; // message pointer
+};
+
+
+
+/*
+ * SERVICE
+ *
+ **/
+
+// srv->version and srv->index must be already set
+// init unix socket + fill srv->spath
+int32_t ipc_server_init (char **env , struct ipc_service *srv, const char *sname);
+int32_t ipc_server_close (struct ipc_service *srv);
+int32_t ipc_server_close_client (struct ipc_client *p);
+int32_t ipc_server_accept (struct ipc_service *srv, struct ipc_client *p);
+
+// 1 on a recipient socket close
+int32_t ipc_server_read (const struct ipc_client *, struct ipc_message *m);
+int32_t ipc_server_write (const struct ipc_client *, const struct ipc_message *m);
+
+int32_t ipc_server_select (struct ipc_clients * clients, struct ipc_service *srv
+        , struct ipc_clients *active_clients, int32_t *new_connection);
+
+int32_t ipc_service_poll_event (struct ipc_clients *clients, struct ipc_service *srv
+        , struct ipc_event *event);
+
+/**
+ * SERVICES
+ */
+
+// store and remove only pointers on allocated structures
+int32_t ipc_services_add (struct ipc_services *, struct ipc_service *);
+int32_t ipc_services_del (struct ipc_services *, struct ipc_service *);
+
+void ipc_services_free  (struct ipc_services *);
+
+struct ipc_service * ipc_client_server_copy (const struct ipc_service *p);
+int32_t ipc_service_eq (const struct ipc_service *p1, const struct ipc_service *p2);
+// create the client service structure
+void ipc_client_server_gen (struct ipc_service *p, uint32_t index, uint32_t version);
+
+static inline int32_t ipc_service_empty (struct ipc_service *srv) { srv = srv; return 0 ;};
+
+
+/*
+ * APPLICATION
+ *
+ **/
+
+// Initialize connection with unix socket
+// send the connection string to $TMP/<service>
+// fill srv->spath && srv->service_fd
+int32_t ipc_application_connection (char **env, struct ipc_service *, const char *);
+int32_t ipc_application_close (struct ipc_service *);
+
+// 1 on a recipient socket close
+int32_t ipc_application_read (struct ipc_service *srv, struct ipc_message *m);
+int32_t ipc_application_write (struct ipc_service *, const struct ipc_message *m);
+
+int32_t ipc_application_select (struct ipc_services *services, struct ipc_services *active_services);
+int32_t ipc_application_poll_event (struct ipc_services *services, struct ipc_event *event);
+int32_t ipc_application_peek_event (struct ipc_services *services, struct ipc_event *event);
+
+
+
+/*
+ * MESSAGE
+ *
+ **/
+
+// used to create msg structure from buffer
+int32_t ipc_message_format_read (struct ipc_message *m, const char *buf, ssize_t msize);
+// used to create buffer from msg structure
+int32_t ipc_message_format_write (const struct ipc_message *m, char **buf, ssize_t *msize);
+
+// read a structure msg from fd
+int32_t ipc_message_read (int32_t fd, struct ipc_message *m);
+// write a structure msg to fd
+int32_t ipc_message_write (int32_t fd, const struct ipc_message *m);
+
+int32_t ipc_message_format (struct ipc_message *m, char type, const char *payload, ssize_t length);
+int32_t ipc_message_format_data (struct ipc_message *m, const char *payload, ssize_t length);
+int32_t ipc_message_format_server_close (struct ipc_message *m);
+
+int32_t ipc_message_empty (struct ipc_message *m);
+
+
+
+/*
+ * CLIENT
+ *
+ **/
+
+// store and remove only pointers on allocated structures
+int32_t ipc_clients_add (struct ipc_clients *, struct ipc_client *);
+int32_t ipc_clients_del (struct ipc_clients *, struct ipc_client *);
+
+void ipc_clients_free  (struct ipc_clients *);
+
+struct ipc_client * ipc_server_client_copy (const struct ipc_client *p);
+int32_t ipc_server_client_eq (const struct ipc_client *p1, const struct ipc_client *p2);
+// create the service client structure
+void ipc_server_client_gen (struct ipc_client *p, uint32_t index, uint32_t version);
+
 
 #endif
diff --git a/core/message.c b/core/message.c
index 613f078..f1dcff5 100644
--- a/core/message.c
+++ b/core/message.c
@@ -12,7 +12,7 @@ void ipc_message_print (const struct ipc_message *m)
 #endif
 }
 
-int ipc_message_format_read (struct ipc_message *m, const char *buf, ssize_t msize)
+int32_t ipc_message_format_read (struct ipc_message *m, const char *buf, ssize_t msize)
 {
     assert (m != NULL);
     assert (buf != NULL);
@@ -43,7 +43,7 @@ int ipc_message_format_read (struct ipc_message *m, const char *buf, ssize_t msi
     return 0;
 }
 
-int ipc_message_format_write (const struct ipc_message *m, char **buf, ssize_t *msize)
+int32_t ipc_message_format_write (const struct ipc_message *m, char **buf, ssize_t *msize)
 {
     assert (m != NULL);
     assert (buf != NULL);
@@ -82,14 +82,14 @@ int ipc_message_format_write (const struct ipc_message *m, char **buf, ssize_t *
 }
 
 // 1 on a recipient socket close
-int ipc_message_read (int fd, struct ipc_message *m)
+int32_t ipc_message_read (int32_t fd, struct ipc_message *m)
 {
     assert (m != NULL);
 
     char *buf = NULL;
     ssize_t msize = IPC_MAX_MESSAGE_SIZE;
 
-    int ret = usock_recv (fd, &buf, &msize);
+    int32_t ret = usock_recv (fd, &buf, &msize);
     if (ret < 0) {
 		// on error, buffer already freed
         handle_err ("msg_read", "usock_recv");
@@ -109,7 +109,7 @@ int ipc_message_read (int fd, struct ipc_message *m)
     return 0;
 }
 
-int ipc_message_write (int fd, const struct ipc_message *m)
+int32_t ipc_message_write (int32_t fd, const struct ipc_message *m)
 {
     assert (m != NULL);
 
@@ -118,7 +118,7 @@ int ipc_message_write (int fd, const struct ipc_message *m)
     ipc_message_format_write (m, &buf, &msize);
 
 	ssize_t nbytes_sent = 0;
-    int ret = usock_send (fd, buf, msize, &nbytes_sent);
+    int32_t ret = usock_send (fd, buf, msize, &nbytes_sent);
     if (ret < 0) {
 		if (buf != NULL) {
 			free (buf);
@@ -145,7 +145,7 @@ int ipc_message_write (int fd, const struct ipc_message *m)
 
 // MSG FORMAT
 
-int ipc_message_format (struct ipc_message *m, char type, const char *payload, ssize_t length)
+int32_t ipc_message_format (struct ipc_message *m, char type, const char *payload, ssize_t length)
 {
     assert (m != NULL);
     assert (length <= IPC_MAX_MESSAGE_SIZE);
@@ -157,7 +157,7 @@ int ipc_message_format (struct ipc_message *m, char type, const char *payload, s
     }
 
     m->type = type;
-    m->length = (unsigned int) length;
+    m->length = (uint32_t) length;
 
     if (payload != NULL) {
 		if (m->payload != NULL) {
@@ -177,17 +177,17 @@ int ipc_message_format (struct ipc_message *m, char type, const char *payload, s
     return 0;
 }
 
-int ipc_message_format_data (struct ipc_message *m, const char *payload, ssize_t length)
+int32_t ipc_message_format_data (struct ipc_message *m, const char *payload, ssize_t length)
 {
     return ipc_message_format (m, MSG_TYPE_DATA, payload, length);
 }
 
-int ipc_message_format_server_close (struct ipc_message *m)
+int32_t ipc_message_format_server_close (struct ipc_message *m)
 {
     return ipc_message_format (m, MSG_TYPE_SERVER_CLOSE, NULL, 0);
 }
 
-int ipc_message_empty (struct ipc_message *m)
+int32_t ipc_message_empty (struct ipc_message *m)
 {
     assert (m != NULL);
 
diff --git a/core/message.h b/core/message.h
index 5f6216a..2aeac2a 100644
--- a/core/message.h
+++ b/core/message.h
@@ -5,37 +5,9 @@
 #include <stdlib.h>
 #include <string.h>
 
-// the underlying communication must always correctly handled by the system
-// (currently: unix sockets)
+#include <stdint.h>
 
-enum msg_types {
-	MSG_TYPE_SERVER_CLOSE = 0
-	, MSG_TYPE_ERR
-	, MSG_TYPE_DATA
-} message_types;
-
-struct ipc_message {
-    char type;
-    unsigned int length;
-    char *payload;
-};
-
-// used to create msg structure from buffer
-int ipc_message_format_read (struct ipc_message *m, const char *buf, ssize_t msize);
-// used to create buffer from msg structure
-int ipc_message_format_write (const struct ipc_message *m, char **buf, ssize_t *msize);
-
-// read a structure msg from fd
-// 1 on a recipient socket close
-int ipc_message_read (int fd, struct ipc_message *m);
-// write a structure msg to fd
-int ipc_message_write (int fd, const struct ipc_message *m);
-
-int ipc_message_format (struct ipc_message *m, char type, const char *payload, ssize_t length);
-int ipc_message_format_data (struct ipc_message *m, const char *payload, ssize_t length);
-int ipc_message_format_server_close (struct ipc_message *m);
-
-int ipc_message_empty (struct ipc_message *m);
+#include "ipc.h"
 void ipc_message_print (const struct ipc_message *m);
 
 #endif
diff --git a/core/usocket.c b/core/usocket.c
index ce15cb6..d553c66 100644
--- a/core/usocket.c
+++ b/core/usocket.c
@@ -8,7 +8,7 @@
 #include <unistd.h>
 #include <assert.h>
 
-int usock_send (const int fd, const char *buf, ssize_t len, ssize_t *sent)
+int32_t usock_send (const int32_t fd, const char *buf, ssize_t len, ssize_t *sent)
 {
     ssize_t ret = 0;
     ret = send (fd, buf, len, MSG_NOSIGNAL);
@@ -21,7 +21,7 @@ int usock_send (const int fd, const char *buf, ssize_t len, ssize_t *sent)
 }
 
 // *len is changed to the total message size read (header + payload)
-int usock_recv (const int fd, char **buf, ssize_t *len)
+int32_t usock_recv (const int32_t fd, char **buf, ssize_t *len)
 {
     assert(buf != NULL);
     assert(len != NULL);
@@ -47,8 +47,8 @@ int usock_recv (const int fd, char **buf, ssize_t *len)
         *buf = malloc (*len + IPC_HEADER_SIZE);
     }
 
-	unsigned int msize = 0;
-	unsigned int msize_read = 0;
+	uint32_t msize = 0;
+	uint32_t msize_read = 0;
 
 	do {
 		ret = recv (fd, *buf, *len, 0);
@@ -135,12 +135,12 @@ int usock_recv (const int fd, char **buf, ssize_t *len)
 		return 1;
 	}
 
-    // print_hexa ("msg recv", (unsigned char *)*buf, *len);
+    // print_hexa ("msg recv", (uint8_t *)*buf, *len);
     // fflush(stdout);
     return 0;
 }
 
-int usock_connect (int *fd, const char *path)
+int32_t usock_connect (int32_t *fd, const char *path)
 {
     assert (fd != NULL);
     assert (path != NULL);
@@ -155,7 +155,7 @@ int usock_connect (int *fd, const char *path)
         return -1;
     }
 
-    int sfd;
+    int32_t sfd;
     struct sockaddr_un my_addr;
     socklen_t peer_addr_size;
 
@@ -183,7 +183,7 @@ int usock_connect (int *fd, const char *path)
     return 0;
 }
 
-int usock_init (int *fd, const char *path)
+int32_t usock_init (int32_t *fd, const char *path)
 {
     assert (fd != NULL);
     assert (path != NULL);
@@ -198,7 +198,7 @@ int usock_init (int *fd, const char *path)
         return -1;
     }
 
-    int sfd;
+    int32_t sfd;
     struct sockaddr_un my_addr;
     socklen_t peer_addr_size;
 
@@ -236,7 +236,7 @@ int usock_init (int *fd, const char *path)
     return 0;
 }
 
-int usock_accept (int fd, int *pfd)
+int32_t usock_accept (int32_t fd, int32_t *pfd)
 {
     assert (pfd != NULL);
 
@@ -259,9 +259,9 @@ int usock_accept (int fd, int *pfd)
     return 0;
 }
 
-int usock_close (int fd)
+int32_t usock_close (int32_t fd)
 {
-    int ret = 0;
+    int32_t ret = 0;
 
 	ret = close (fd);
     if (ret < 0) {
@@ -272,7 +272,7 @@ int usock_close (int fd)
     return 0;
 }
 
-int usock_remove (const char *path)
+int32_t usock_remove (const char *path)
 {
     return unlink (path);
 }
@@ -292,20 +292,20 @@ struct ipc_service * ipc_client_server_copy (const struct ipc_service *p)
     return copy;
 }
 
-int ipc_client_server_eq (const struct ipc_service *p1, const struct ipc_service *p2)
+int32_t ipc_client_server_eq (const struct ipc_service *p1, const struct ipc_service *p2)
 {
     return (p1->version == p2->version && p1->index == p2->index
             && p1->service_fd == p2->service_fd && memcmp(p1->spath, p1->spath, PATH_MAX) == 0 );
 }
 
 void ipc_client_server_gen (struct ipc_service *p
-        , unsigned int index, unsigned int version)
+        , uint32_t index, uint32_t version)
 {
     p->version = version;
     p->index = index;
 }
 
-int ipc_service_add (struct ipc_services *services, struct ipc_service *p)
+int32_t ipc_services_add (struct ipc_services *services, struct ipc_service *p)
 {
     assert(services != NULL);
     assert(p != NULL);
@@ -322,7 +322,7 @@ int ipc_service_add (struct ipc_services *services, struct ipc_service *p)
     return 0;
 }
 
-int ipc_service_del (struct ipc_services *services, struct ipc_service *p)
+int32_t ipc_services_del (struct ipc_services *services, struct ipc_service *p)
 {
     assert(services != NULL);
     assert(p != NULL);
@@ -331,7 +331,7 @@ int ipc_service_del (struct ipc_services *services, struct ipc_service *p)
         return -1;
     }
 
-    int i;
+    int32_t i;
     for (i = 0; i < services->size; i++) {
         if (services->services[i] == p) {
 
@@ -365,7 +365,7 @@ void service_print (struct ipc_service *p)
 
 void ipc_services_print (struct ipc_services *ap)
 {
-    int i;
+    int32_t i;
     for (i = 0; i < ap->size; i++) {
         printf("%d : ", i);
         service_print(ap->services[i]);
diff --git a/core/usocket.h b/core/usocket.h
index 4dbc8e5..370eebb 100644
--- a/core/usocket.h
+++ b/core/usocket.h
@@ -5,33 +5,18 @@
 #include <sys/socket.h>
 #include <sys/un.h>
 
+#include "ipc.h"
+#include <stdint.h>
+
 #define LISTEN_BACKLOG 128
 
-#define RUNDIR "/run/ipc/"
-#define PATH_MAX 4096
-
-#define IPC_HEADER_SIZE  5
-#define IPC_MAX_MESSAGE_SIZE  8000000-IPC_HEADER_SIZE
-
-struct ipc_service {
-    unsigned int version;
-    unsigned int index;
-    char spath[PATH_MAX];
-    int service_fd;
-};
-
-struct ipc_services {
-	struct ipc_service ** services;
-	int size;
-};
-
 /**
  * for all functions: 0 ok, < 0 not ok
  */
 
 // input:  len   = max buf size
 // output: *sent = nb received bytes
-int usock_send (const int fd, const char *buf, ssize_t len, ssize_t *sent);
+int32_t usock_send (const int32_t fd, const char *buf, ssize_t len, ssize_t *sent);
 
 // -1 on msize == NULL or buf == NULL
 // -1 on unsupported errors from read(2)
@@ -40,38 +25,23 @@ int usock_send (const int fd, const char *buf, ssize_t len, ssize_t *sent);
 // allocation of *len bytes on *buf == NULL
 //
 // output: *len = nb sent bytes
-int usock_recv (int fd, char **buf, ssize_t *len);
+int32_t usock_recv (int32_t fd, char **buf, ssize_t *len);
 
 // -1 on close(2) < 0
-int usock_close (int fd);
+int32_t usock_close (int32_t fd);
 
 // same as connect(2)
 // -1 on fd == NULL
-int usock_connect (int *fd, const char *path);
+int32_t usock_connect (int32_t *fd, const char *path);
 
-int usock_init (int *fd, const char *path);
+int32_t usock_init (int32_t *fd, const char *path);
 
-int usock_accept (int fd, int *pfd);
+int32_t usock_accept (int32_t fd, int32_t *pfd);
 
 // same as unlink(2)
-int usock_remove (const char *path);
-
-static inline int ipc_service_empty (struct ipc_service *srv) { srv = srv; return 0 ;};
-
-
-// store and remove only pointers on allocated structures
-int ipc_service_add (struct ipc_services *, struct ipc_service *);
-int ipc_service_del (struct ipc_services *, struct ipc_service *);
+int32_t usock_remove (const char *path);
 
 void ipc_services_print (struct ipc_services *);
-void ipc_services_free  (struct ipc_services *);
-
-struct ipc_service * ipc_client_server_copy (const struct ipc_service *p);
-int ipc_service_eq (const struct ipc_service *p1, const struct ipc_service *p2);
-// create the client service structure
-void ipc_client_server_gen (struct ipc_service *p
-        , unsigned int index, unsigned int version);
-
 void service_print (struct ipc_service *);
 
 #endif
diff --git a/core/utils.c b/core/utils.c
index fe97b83..d6c5f37 100644
--- a/core/utils.c
+++ b/core/utils.c
@@ -1,6 +1,6 @@
 #include "utils.h"
 
-void print_hexa (const char *prefix, unsigned char *payload, size_t size)
+void print_hexa (const char *prefix, uint8_t *payload, size_t size)
 {
     if (! payload)
         return ;
@@ -16,7 +16,7 @@ void print_hexa (const char *prefix, unsigned char *payload, size_t size)
 }
 
 
-void mprint_hexa (char *prefix, unsigned char *buf, size_t length)
+void mprint_hexa (char *prefix, uint8_t *buf, size_t length)
 {
     print_hexa (prefix, buf, length);
 }
diff --git a/core/utils.h b/core/utils.h
index 486575d..352b78f 100644
--- a/core/utils.h
+++ b/core/utils.h
@@ -5,7 +5,9 @@
 #include <stdlib.h>
 #include <string.h>
 
-void print_hexa (const char *prefix, unsigned char *payload, size_t size);
-void mprint_hexa (char *prefix, unsigned char *buf, size_t length);
+#include <stdint.h>
+
+void print_hexa (const char *prefix, uint8_t *payload, size_t size);
+void mprint_hexa (char *prefix, uint8_t *buf, size_t length);
 
 #endif
diff --git a/drop/init-connection.c b/drop/init-connection.c
index 8cfb268..16f28aa 100644
--- a/drop/init-connection.c
+++ b/drop/init-connection.c
@@ -3,12 +3,12 @@
 #define SERVICE         "windowing"
 
 void
-ohshit(int rvalue, const char* str) {
+ohshit(int32_t rvalue, const char* str) {
     fprintf(stderr, "%s\n", str);
     exit(rvalue);
 }
 
-int main(int argc, char * argv[], char *env[])
+int32_t main(int32_t argc, char * argv[], char *env[])
 {
     struct ipc_service srv;
     memset (&srv, 0, sizeof (struct ipc_service));
@@ -26,8 +26,8 @@ int main(int argc, char * argv[], char *env[])
     struct ipc_client p;
     memset (&p, 0, sizeof (struct ipc_client));
 
-    int index = 0; // first time we communication with the service
-    int version = 1;
+    int32_t index = 0; // first time we communication with the service
+    int32_t version = 1;
 
     printf ("app creation\n");
     if (application_create (&p, index, version)) // called by the application
diff --git a/drop/list.c b/drop/list.c
index 71dbda0..501e6bd 100644
--- a/drop/list.c
+++ b/drop/list.c
@@ -7,11 +7,11 @@ LIST_HEAD(mlist, node);
 
 // elements structure of the list
 struct node {
-    int content;
+    int32_t content;
     LIST_ENTRY(node) entries;
 };
 
-int main(int argc, char * argv[])
+int32_t main(int32_t argc, char * argv[])
 {
     (void) argc;
     (void) argv;
diff --git a/drop/msg.c b/drop/msg.c
index 4452934..1edde58 100644
--- a/drop/msg.c
+++ b/drop/msg.c
@@ -8,7 +8,7 @@
 #define PKT_ERROR                   2
 
 void
-ohshit(int rvalue, const char* str) {
+ohshit(int32_t rvalue, const char* str) {
     fprintf (stderr, "\033[31merr: %s\033[00m\n", str);
     exit (rvalue);
 }
@@ -21,15 +21,15 @@ void usage (char **argv)
     printf ( "    This sends a CBOR msg [ 1, \"data\" ]\n");
 }
 
-int
-main(int argc, char **argv)
+int32_t
+main(int32_t argc, char **argv)
 {
     if (argc == 2 && strcmp ("-h", argv[1]) == 0) {
         usage (argv);
         exit (1);
     }
 
-    unsigned char buf[BUFSIZ];
+    uint8_t buf[BUFSIZ];
     memset (buf, 0, BUFSIZ);
 
     ssize_t buflen = read (0, buf, BUFSIZ);
@@ -42,7 +42,7 @@ main(int argc, char **argv)
             .value = cbor_move(cbor_build_bytestring(buf, buflen))
             });
     /* Output: `length` bytes of data in the `buffer` */
-    unsigned char * buffer;
+    uint8_t * buffer;
     size_t buffer_size, length = cbor_serialize_alloc (root, &buffer, &buffer_size);
 
     fwrite(buffer, 1, length, stdout);
diff --git a/drop/open-read-close-fifo.c b/drop/open-read-close-fifo.c
index ca2f396..ada2cd1 100644
--- a/drop/open-read-close-fifo.c
+++ b/drop/open-read-close-fifo.c
@@ -3,7 +3,7 @@
 #include <string.h>
 #include <unistd.h>
 
-int main(int argc, char * argv[])
+int32_t main(int32_t argc, char * argv[])
 {
 
     (void) argc;
diff --git a/drop/open-write-close-fifo.c b/drop/open-write-close-fifo.c
index ca4c950..d8e94e4 100644
--- a/drop/open-write-close-fifo.c
+++ b/drop/open-write-close-fifo.c
@@ -3,7 +3,7 @@
 #include <string.h>
 #include <unistd.h>
 
-int main(int argc, char * argv[])
+int32_t main(int32_t argc, char * argv[])
 {
     (void) argc;
     (void) argv;
diff --git a/drop/pass-socket_client.c b/drop/pass-socket_client.c
index ebe3d8d..3fa2d76 100644
--- a/drop/pass-socket_client.c
+++ b/drop/pass-socket_client.c
@@ -64,7 +64,7 @@ void log_debug (const char* message, ...) {
 }
 
 static
-int recvsockfd (int socket)  // receive fd from socket
+int32_t recvsockfd (int32_t socket)  // receive fd from socket
 {
     struct ipc_messagehdr msg = {0};
 
@@ -84,14 +84,14 @@ int recvsockfd (int socket)  // receive fd from socket
     struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg);
 
     printf ("About to extract fd\n");
-    int fd;
+    int32_t fd;
     memmove(&fd, CMSG_DATA(cmsg), sizeof(fd));
     printf ("Extracted fd %d\n", fd);
 
     return fd;
 }
 
-int usock_connect (int *fd, const char *path)
+int32_t usock_connect (int32_t *fd, const char *path)
 {
     assert (fd != NULL);
     assert (path != NULL);
@@ -106,7 +106,7 @@ int usock_connect (int *fd, const char *path)
         return -1;
     }
 
-    int sfd;
+    int32_t sfd;
     struct sockaddr_un my_addr;
     socklen_t peer_addr_size;
 
@@ -134,7 +134,7 @@ int usock_connect (int *fd, const char *path)
     return 0;
 }
 
-int usock_init (int *fd, const char *path)
+int32_t usock_init (int32_t *fd, const char *path)
 {
     assert (fd != NULL);
     assert (path != NULL);
@@ -149,7 +149,7 @@ int usock_init (int *fd, const char *path)
         return -1;
     }
 
-    int sfd;
+    int32_t sfd;
     struct sockaddr_un my_addr;
     socklen_t peer_addr_size;
 
@@ -187,7 +187,7 @@ int usock_init (int *fd, const char *path)
     return 0;
 }
 
-int usock_accept (int fd, int *pfd)
+int32_t usock_accept (int32_t fd, int32_t *pfd)
 {
     assert (pfd != NULL);
 
@@ -210,9 +210,9 @@ int usock_accept (int fd, int *pfd)
     return 0;
 }
 
-int usock_close (int fd)
+int32_t usock_close (int32_t fd)
 {
-    int ret;
+    int32_t ret;
     ret = close (fd);
     if (ret < 0) {
         handle_err ("usock_close", "close ret < 0");
@@ -221,15 +221,15 @@ int usock_close (int fd)
     return ret;
 }
 
-int usock_remove (const char *path)
+int32_t usock_remove (const char *path)
 {
     return unlink (path);
 }
 
-int main(int argc, char * argv[])
+int32_t main(int32_t argc, char * argv[])
 {
-    int tcpsockfd;
-    int usockfd;
+    int32_t tcpsockfd;
+    int32_t usockfd;
     // check the number of args on command line
     if(argc != 1)
     {
@@ -240,7 +240,7 @@ int main(int argc, char * argv[])
     printf("Connection to the unix socket\n");
 
     // 1. unix socket connection
-    int ret = usock_connect (&usockfd, USOCK);
+    int32_t ret = usock_connect (&usockfd, USOCK);
     if (ret != 0) {
         fprintf (stderr, "error: usock_connect\n");
         exit(EXIT_FAILURE);
diff --git a/drop/pass-socket_server.c b/drop/pass-socket_server.c
index e1259f5..19d0002 100644
--- a/drop/pass-socket_server.c
+++ b/drop/pass-socket_server.c
@@ -63,9 +63,9 @@ void log_debug (const char* message, ...) {
     va_end(args);
 }
 
-int build_socket (char *servername, char * serverport)
+int32_t build_socket (char *servername, char * serverport)
 {
-    int sockfd;
+    int32_t sockfd;
     struct sockaddr_in6 server;
     socklen_t addrlen;
 
@@ -99,7 +99,7 @@ int build_socket (char *servername, char * serverport)
     return sockfd;
 }
 
-int usock_connect (int *fd, const char *path)
+int32_t usock_connect (int32_t *fd, const char *path)
 {
     assert (fd != NULL);
     assert (path != NULL);
@@ -114,7 +114,7 @@ int usock_connect (int *fd, const char *path)
         return -1;
     }
 
-    int sfd;
+    int32_t sfd;
     struct sockaddr_un my_addr;
     socklen_t peer_addr_size;
 
@@ -142,7 +142,7 @@ int usock_connect (int *fd, const char *path)
     return 0;
 }
 
-int usock_init (int *fd, const char *path)
+int32_t usock_init (int32_t *fd, const char *path)
 {
     assert (fd != NULL);
     assert (path != NULL);
@@ -157,7 +157,7 @@ int usock_init (int *fd, const char *path)
         return -1;
     }
 
-    int sfd;
+    int32_t sfd;
     struct sockaddr_un my_addr;
     socklen_t peer_addr_size;
 
@@ -195,7 +195,7 @@ int usock_init (int *fd, const char *path)
     return 0;
 }
 
-int usock_accept (int fd, int *pfd)
+int32_t usock_accept (int32_t fd, int32_t *pfd)
 {
     assert (pfd != NULL);
 
@@ -218,9 +218,9 @@ int usock_accept (int fd, int *pfd)
     return 0;
 }
 
-int usock_close (int fd)
+int32_t usock_close (int32_t fd)
 {
-    int ret;
+    int32_t ret;
     ret = close (fd);
     if (ret < 0) {
         handle_err ("usock_close", "close ret < 0");
@@ -229,14 +229,14 @@ int usock_close (int fd)
     return ret;
 }
 
-int usock_remove (const char *path)
+int32_t usock_remove (const char *path)
 {
     return unlink (path);
 }
 
-int build_unix_socket (char * path)
+int32_t build_unix_socket (char * path)
 {
-    int remotefd, localfd;
+    int32_t remotefd, localfd;
 
     usock_init (&localfd, path);
     usock_accept (localfd, &remotefd);
@@ -245,7 +245,7 @@ int build_unix_socket (char * path)
 }
 
 static
-void sendfd (int socket, int fd)  // send fd by socket
+void sendfd (int32_t socket, int32_t fd)  // send fd by socket
 {
     struct ipc_messagehdr msg = { 0 };
     char buf[CMSG_SPACE(sizeof(fd))];
@@ -272,7 +272,7 @@ void sendfd (int socket, int fd)  // send fd by socket
         handle_err("sendfd", "Failed to send message\n");
 }
 
-int main(int argc, char * argv[])
+int32_t main(int32_t argc, char * argv[])
 {
     // check the number of args on command line
     if(argc != 3)
@@ -285,7 +285,7 @@ int main(int argc, char * argv[])
 
     printf("Connection to the tcp socket\n");
     // 1. socket creation (tcp), connection to the server
-    int sockfd = build_socket (servername, serverport);
+    int32_t sockfd = build_socket (servername, serverport);
 
     printf("Sending 'coucou' to the tcp socket\n");
     // send a message to check the connection is effective
@@ -297,7 +297,7 @@ int main(int argc, char * argv[])
 
     printf ("Connection to the unix socket\n");
     // 2. socket creation (unix)
-    int usockfd = build_unix_socket (USOCK);
+    int32_t usockfd = build_unix_socket (USOCK);
 
     printf ("Passing the tcp socket to the unix socket\n");
     // 3. tcp socket passing to the client
diff --git a/drop/readmsg.c b/drop/readmsg.c
index fb170e9..cb16edb 100644
--- a/drop/readmsg.c
+++ b/drop/readmsg.c
@@ -12,7 +12,7 @@ void usage (char **argv) {
     printf ("usage: echo something | msg | %s\n", argv[0]);
 }
 
-int main(int argc, char * argv[])
+int32_t main(int32_t argc, char * argv[])
 {
     if (argc == 2 && strcmp ("-h", argv[1]) == 0) {
         usage (argv);
@@ -21,7 +21,7 @@ int main(int argc, char * argv[])
 
     // read the message from the client
     size_t mlen = 0;
-    unsigned char buf[BUFSIZ];
+    uint8_t buf[BUFSIZ];
     mlen = read (0, buf, BUFSIZ);
 
     /* Assuming `buffer` contains `info.st_size` bytes of input data */
diff --git a/drop/tcpselect.c b/drop/tcpselect.c
index e1c2479..0065828 100644
--- a/drop/tcpselect.c
+++ b/drop/tcpselect.c
@@ -11,7 +11,7 @@
 
 #define PORT 2020
 
-int main(int argc, char *argv[])
+int32_t main(int32_t argc, char *argv[])
 {
     /* master file descriptor list */
     fd_set master;
@@ -23,19 +23,19 @@ int main(int argc, char *argv[])
     struct sockaddr_in clientaddr;
 
     /* maximum file descriptor number */
-    int fdmax;
+    int32_t fdmax;
     /* listening socket descriptor */
-    int listener;
+    int32_t listener;
     /* newly accept()ed socket descriptor */
-    int newfd;
+    int32_t newfd;
     /* buffer for client data */
     char buf[1024];
-    int nbytes;
+    int32_t nbytes;
 
     /* for setsockopt() SO_REUSEADDR, below */
-    int yes = 1;
-    int addrlen;
-    int i, j;
+    int32_t yes = 1;
+    int32_t addrlen;
+    int32_t i, j;
 
     /* clear the master and temp sets */
     FD_ZERO(&master);
@@ -50,7 +50,7 @@ int main(int argc, char *argv[])
 
     printf("Server-socket() is OK...\n");
     /*"address already in use" error message */
-    if(setsockopt(listener, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) == -1)
+    if(setsockopt(listener, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int32_t)) == -1)
     {
         perror("Server-setsockopt() error lol!");
         exit(1);
diff --git a/man/communication.h.3 b/man/communication.h.3
index ccdb14c..f3b9db5 100644
--- a/man/communication.h.3
+++ b/man/communication.h.3
@@ -5,25 +5,25 @@ communication.h \- all functions explained
 .nf
 .B #include <communication.h>
 .sp
-.BI "int ipc_server_init (int "argc ", char **" argv ", char **" env ", struct ipc_service *" srv "
+.BI "int32_t ipc_server_init (int32_t "argc ", char **" argv ", char **" env ", struct ipc_service *" srv "
 .BI "       , const char *" service_name );
-.BI "int ipc_server_accept (struct ipc_service *" srv ", struct ipc_client *" p );
+.BI "int32_t ipc_server_accept (struct ipc_service *" srv ", struct ipc_client *" p );
 .sp
-.BI "int ipc_server_read (const struct ipc_client *" p ", struct ipc_message *" message );
-.BI "int ipc_server_write (const struct ipc_client *" p ", const struct ipc_message *" message );
+.BI "int32_t ipc_server_read (const struct ipc_client *" p ", struct ipc_message *" message );
+.BI "int32_t ipc_server_write (const struct ipc_client *" p ", const struct ipc_message *" message );
 .sp
-.BI "int ipc_server_close (struct ipc_service *" srv );
-.BI "int ipc_server_close_client (struct ipc_client *" p );
-.BI "int ipc_server_select (struct ipc_clients *" fds ", struct ipc_service *" srv ", struct ipc_clients *" readfds );
+.BI "int32_t ipc_server_close (struct ipc_service *" srv );
+.BI "int32_t ipc_server_close_client (struct ipc_client *" p );
+.BI "int32_t ipc_server_select (struct ipc_clients *" fds ", struct ipc_service *" srv ", struct ipc_clients *" readfds );
 
-.BI "int ipc_application_connection (int " argc ", char **" argv ", char **" env ", struct ipc_service *" srv
+.BI "int32_t ipc_application_connection (int32_t " argc ", char **" argv ", char **" env ", struct ipc_service *" srv
 .BI "       , const char *" service_name "
 .BI "       , const char *" connection_buffer ", size_t " bufsize );
 .sp
-.BI "int ipc_application_read (const struct ipc_service *" srv ", struct ipc_message *" message );
-.BI "int ipc_application_write (const struct ipc_service *" srv ", const struct ipc_message *" message );
+.BI "int32_t ipc_application_read (const struct ipc_service *" srv ", struct ipc_message *" message );
+.BI "int32_t ipc_application_write (const struct ipc_service *" srv ", const struct ipc_message *" message );
 .sp
-.BI "int ipc_application_close (struct ipc_service *" srv );
+.BI "int32_t ipc_application_close (struct ipc_service *" srv );
 
 
 .fi
diff --git a/pong/app/ipc-debug.c b/pong/app/ipc-debug.c
index d4b4d14..28701a9 100644
--- a/pong/app/ipc-debug.c
+++ b/pong/app/ipc-debug.c
@@ -5,6 +5,8 @@
 #include <readline/readline.h>
 #include <readline/history.h>
 
+#include <stdint.h>
+
 #include "../../core/communication.h"
 #include "../../core/error.h"
 
@@ -35,7 +37,7 @@ void interactive (char * service_name, char *env[])
 
 	struct ipc_services services;
 	memset (&services, 0, sizeof (struct ipc_services));
-	ipc_service_add (&services, &srv);
+	ipc_services_add (&services, &srv);
 	int ret = 0;
 
     while (1) {
diff --git a/pong/app/pong.c b/pong/app/pong.c
index f863238..3a458f6 100644
--- a/pong/app/pong.c
+++ b/pong/app/pong.c
@@ -4,6 +4,7 @@
 #include <unistd.h>
 
 #include "../../core/ipc.h"
+#include "../../core/error.h"
 
 #define MSG "coucou"
 #define SERVICE_NAME "pongd"
@@ -70,7 +71,7 @@ void interactive (char *env[])
 
 	struct ipc_services services;
 	memset (&services, 0, sizeof (struct ipc_services));
-	ipc_service_add (&services, &srv);
+	ipc_services_add (&services, &srv);
 
     while (1) {
         printf ("msg to send: ");
diff --git a/pong/app/pongd.c b/pong/app/pongd.c
index 0c09780..8d83e45 100644
--- a/pong/app/pongd.c
+++ b/pong/app/pongd.c
@@ -1,4 +1,5 @@
 #include "../../core/ipc.h"
+#include "../../core/error.h"
 #include <signal.h>
 
 #include <sys/socket.h>
@@ -6,6 +7,7 @@
 #include <unistd.h>
 
 #define PONGD_SERVICE_NAME "pongd"
+#define PONGD_PRINT_MESSAGES
 
 int cpt = 0;
 
@@ -41,14 +43,18 @@ void main_loop ()
 			case IPC_EVENT_TYPE_CONNECTION:
 				{
 					cpt++;
-					printf ("connection: %d clients connected\n", cpt);
-					printf ("new client has the fd %d\n", ((struct ipc_client*) event.origin)->proc_fd);
+#ifdef PONGD_PRINT_MESSAGES
+					 printf ("connection: client fd %d, %d clients connected\n"
+							 , ((struct ipc_client*) event.origin)->proc_fd, cpt);
+#endif
 				};
 				break;
 			case IPC_EVENT_TYPE_DISCONNECTION:
 				{
 					cpt--;
+#ifdef PONGD_PRINT_MESSAGES
 					printf ("disconnection: %d clients remaining\n", cpt);
+#endif
 
 					// free the ipc_client structure
 					free (event.origin);
@@ -57,9 +63,11 @@ void main_loop ()
 			case IPC_EVENT_TYPE_MESSAGE:
 			   	{
 					struct ipc_message *m = event.m;
+#ifdef PONGD_PRINT_MESSAGES
 					if (m->length > 0) {
 						printf ("message received (type %d): %.*s\n", m->type, m->length, m->payload);
 					}
+#endif
 					if (ipc_server_write (event.origin, m) < 0) {
 						handle_err( "handle_new_msg", "server_write < 0");
 					}
diff --git a/pong/app/test-exchange.c b/pong/app/test-exchange.c
new file mode 100644
index 0000000..b90f67a
--- /dev/null
+++ b/pong/app/test-exchange.c
@@ -0,0 +1,106 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <readline/readline.h>
+#include <readline/history.h>
+
+#include <stdint.h>
+
+#include "../../core/communication.h"
+#include "../../core/error.h"
+
+#define SERVICE_NAME "pongd"
+
+#define NUMBER_OF_MESSAGES 1000
+#define MAX_MESSAGE_SIZE  IPC_MAX_MESSAGE_SIZE
+#define MESSAGE "salut ça va ?"
+
+void non_interactive (char msg_type, char *msg, char * service_name, char *env[])
+{
+    struct ipc_message m;
+    memset (&m, 0, sizeof (struct ipc_message));
+    struct ipc_service srv;
+    memset (&srv, 0, sizeof (struct ipc_service));
+
+    // index and version should be filled
+    srv.index = 0;
+    srv.version = 0;
+
+    // init service
+    if (ipc_application_connection (env, &srv, service_name) < 0) {
+        handle_err ("main", "ipc_application_connection < 0");
+        exit (EXIT_FAILURE);
+    }
+
+	for (int i = 0 ; i < NUMBER_OF_MESSAGES ; i++) {
+		ipc_message_format (&m, msg_type, msg, strlen(msg) + 1);
+		// print_msg (&m);
+
+		if (ipc_application_write (&srv, &m) < 0) {
+			handle_err("main", "application_write < 0");
+			exit (EXIT_FAILURE);
+		}
+		ipc_message_empty (&m);
+
+		if (ipc_application_read (&srv, &m) < 0) {
+			handle_err("main", "application_read < 0");
+			exit (EXIT_FAILURE);
+		}
+
+#ifdef WITH_PRINT_MESSAGES
+		if (m.length > 0) {
+			printf ("msg recv: %.*s\n", m.length, m.payload);
+		}
+#endif
+		ipc_message_empty (&m);
+	}
+
+	if (ipc_application_close (&srv) < 0) {
+        handle_err("main", "application_close < 0");
+        exit (EXIT_FAILURE);
+    }
+	ipc_message_empty (&m);
+}
+
+// usage: ipc-debug [service-name]
+int main (int argc, char *argv[], char *env[])
+{
+	if (argc == 1) {
+		printf ("usage: %s service_name [message-type [message]]\n", argv[0]);
+		exit (EXIT_SUCCESS);
+	}
+
+	char service_name[100];
+	memset (service_name, 0, 100);
+
+	int current_param = 1;
+
+	if (argc != 1) {
+		ssize_t t = strlen(argv[current_param]) > 100 ? 100 : strlen(argv[current_param]);
+		memcpy(service_name, argv[current_param], t);
+		current_param++;
+	}
+	else { memcpy(service_name, SERVICE_NAME, strlen(SERVICE_NAME)); }
+
+	char mtype = 2;
+	if (argc > 2) {
+		mtype = atoi(argv[current_param]);
+		current_param++;
+   	}
+
+	char *msg = malloc (MAX_MESSAGE_SIZE);
+	if (msg == NULL) {
+		handle_err("main", "not enough memory");
+		exit (EXIT_FAILURE);
+	}
+	memset(msg, 0, MAX_MESSAGE_SIZE);
+
+	if (argc > 3) { memcpy(msg, argv[current_param], strlen(argv[current_param])); }
+	else          { memcpy(msg, MESSAGE, strlen(MESSAGE)); }
+
+	non_interactive (mtype, msg, service_name, env);
+	free (msg);
+
+    return EXIT_SUCCESS;
+}