diff --git a/lib/communication.c b/lib/communication.c
index 828cb6f..0faf567 100644
--- a/lib/communication.c
+++ b/lib/communication.c
@@ -5,6 +5,10 @@
 int file_open (FILE **f, const char *path, const char *mode)
 {
     printf ("opening %s\n", path);
+    if (*f != NULL) {
+        printf ("f != NULL : %p\n", *f);
+        fclose (*f);
+    }
     *f = fopen (path, mode);
     if (*f == NULL) {
         fprintf (stderr, "\033[31mnot opened\033[00m\n");
@@ -124,13 +128,13 @@ int srv_get_new_process (const struct service *srv, struct process *p)
 
     printf("diff nsec: %ld\n", ts2.tv_nsec - ts.tv_nsec);
 
-    char *token, *saveptr;
-    char *str;
-    int i;
+    char *token = NULL, *saveptr = NULL;
+    char *str = NULL;
+    int i = 0;
 
-    pid_t pid;
-    int index;
-    int version;
+    pid_t pid = 0;
+    int index = 0;
+    int version = 0;
 
     for (str = buf, i = 1; ; str = NULL, i++) {
         token = strtok_r(str, " ", &saveptr);
@@ -170,6 +174,7 @@ int srv_read_cb (struct process *p, char ** buf, size_t * msize
 
     if (file_close (p->out))
         return 1;
+    p->out = NULL;
 
     return 0;
 }
@@ -184,6 +189,7 @@ int srv_read (struct process *p, char ** buf, size_t * msize)
 
     if (file_close (p->out))
         return 1;
+    p->out = NULL;
 
     return 0;
 }
@@ -197,12 +203,32 @@ int srv_write (struct process *p, void * buf, size_t msize)
 
     if (file_close (p->in))
         return 1;
+    p->in = NULL;
 
     return 0;
 }
 
 // APPLICATION
 
+// send the connection string to $TMP/<service>
+int app_srv_connection (struct service *srv, const char *connectionstr, size_t msize)
+{
+    if (srv == NULL) {
+        return 1;
+    }
+
+    FILE * f = NULL;
+    if (file_open (&f, srv->spath, "wb"))
+        return 2;
+
+    fwrite (connectionstr, msize, 1, f); // FIXME check errors
+
+    if (file_close (f))
+        return 3;
+
+    return 0;
+}
+
 int app_create (struct process *p, int index)
 {
     pid_t pid = getpid();
@@ -303,6 +329,7 @@ int app_read_cb (struct process *p, char ** buf, size_t * msize
 
     if (file_close (p->in))
         return 1;
+    p->in = NULL;
 
     return 0;
 }
@@ -317,6 +344,7 @@ int app_read (struct process *p, void * buf, size_t * msize)
 
     if (file_close (p->in))
         return 1;
+    p->in = NULL;
 
     return 0;
 }
@@ -330,6 +358,7 @@ int app_write (struct process *p, void * buf, size_t msize)
 
     if (file_close (p->out))
         return 1;
+    p->out = NULL;
 
     return 0;
 }
diff --git a/lib/communication.h b/lib/communication.h
index 5241b05..e9139de 100644
--- a/lib/communication.h
+++ b/lib/communication.h
@@ -45,6 +45,9 @@ int srv_write (struct process *, void * buf, size_t);
 
 // APPLICATION
 
+// send the connection string to $TMP/<service>
+int app_srv_connection (struct service *, const char *, size_t);
+
 int app_create (struct process *, int index); // called by the application
 int app_destroy (struct process *); // called by the application
 
diff --git a/lib/process.c b/lib/process.c
index cc81fc1..0548fa3 100644
--- a/lib/process.c
+++ b/lib/process.c
@@ -28,6 +28,8 @@ void srv_process_gen (struct process *p
     bzero (p->path_out, PATH_MAX);
     snprintf(p->path_in , PATH_MAX, "%s/%d-%d-in" , TMPDIR, pid, index);
     snprintf(p->path_out, PATH_MAX, "%s/%d-%d-out", TMPDIR, pid, index);
+    p->in = NULL;
+    p->out = NULL;
 }
 
 void srv_process_free (struct process * p)
diff --git a/lib/pubsubd.c b/lib/pubsubd.c
index ae12610..7c7815f 100644
--- a/lib/pubsubd.c
+++ b/lib/pubsubd.c
@@ -34,7 +34,7 @@ void pubsubd_channels_del_all (struct channels *chans)
     if (!chans)
         return;
 
-    struct channel *c;
+    struct channel *c = NULL;
 
     while (!LIST_EMPTY(chans)) {
         c = LIST_FIRST(chans);
@@ -50,7 +50,7 @@ struct channel * pubsubd_channel_copy (struct channel *c)
     if (c == NULL)
         return NULL;
 
-    struct channel *copy;
+    struct channel *copy = NULL;
     copy = malloc (sizeof(struct channel));
     bzero (copy, sizeof (struct channel));
 
@@ -142,7 +142,7 @@ struct app_list_elm * pubsubd_app_list_elm_copy (const struct app_list_elm *ale)
     if (ale == NULL)
         return NULL;
 
-    struct app_list_elm * n;
+    struct app_list_elm * n = NULL;
     n = malloc (sizeof (struct app_list_elm));
 
     if (ale->p != NULL)
@@ -173,7 +173,7 @@ pubsubd_subscriber_add (struct app_list_head *alh, const struct app_list_elm *al
 struct app_list_elm *
 pubsubd_subscriber_get (const struct app_list_head *chans, const struct app_list_elm *p)
 {
-    struct app_list_elm *np, *res = NULL;
+    struct app_list_elm *np = NULL, *res = NULL;
     LIST_FOREACH(np, chans, entries) {
         if(pubsubd_subscriber_eq (np, p)) {
             res = np;
@@ -199,7 +199,7 @@ void pubsubd_subscriber_del_all (struct app_list_head *alh)
     if (!alh)
         return;
 
-    struct app_list_elm *ale;
+    struct app_list_elm *ale = NULL;
 
     while (!LIST_EMPTY(alh)) {
         ale = LIST_FIRST(alh);
@@ -317,8 +317,8 @@ int pubsubd_get_new_process (struct service *srv, struct app_list_elm *ale
     if (srv == NULL || ale == NULL || chans == NULL)
         return -1;
 
-    char *buf;
-    size_t msize;
+    char *buf = NULL;
+    size_t msize = 0;
     srv_get_listen_raw (srv, &buf, &msize);
 
     // parse pubsubd init msg (sent in TMPDIR/<service>)
@@ -326,12 +326,12 @@ int pubsubd_get_new_process (struct service *srv, struct app_list_elm *ale
     // line fmt : pid index version action chan
     // action : quit | pub | sub
 
-    size_t i;
-    char *str, *token, *saveptr;
+    size_t i = 0;
+    char *str = NULL, *token = NULL, *saveptr = NULL;
 
-    pid_t pid;
-    int index;
-    int version;
+    pid_t pid = 0;
+    int index = 0;
+    int version = 0;
 
     char chan[BUFSIZ];
     bzero (chan, BUFSIZ);
@@ -399,7 +399,7 @@ int pubsubd_get_new_process (struct service *srv, struct app_list_elm *ale
     c[0]->chan = strndup (chan, BUFSIZ);
     c[0]->chanlen = strlen (chan);
 
-    struct channel *new_chan;
+    struct channel *new_chan = NULL;
     new_chan = pubsubd_channel_get (chans, *c);
     if (new_chan == NULL) {
         new_chan = pubsubd_channels_add (chans, *c);
@@ -424,27 +424,29 @@ int pubsubd_msg_read_cb (FILE *f, char ** buf, size_t * msize)
     printf ("\033[36m ON PASSE DANS pubsubd_msg_read_cb \033[00m \n");
 
     // read 
-    char type;
+    char type = ' ';
     fread (&type, 1, 1, f);
 
-    size_t chanlen;
+    size_t chanlen = 0;
     fread (&chanlen, sizeof (size_t), 1, f);
 
     if (chanlen > BUFSIZ) {
         return 1;
     }
 
-    char *chan = malloc (chanlen);
+    char *chan = NULL;
+    chan = malloc (chanlen);
     fread (chan, chanlen, 1, f);
 
-    size_t datalen;
+    size_t datalen = 0;
     fread (&datalen, sizeof (size_t), 1, f);
 
     if (datalen > BUFSIZ) {
         return 1;
     }
 
-    char *data = malloc (datalen);
+    char *data = NULL;
+    data = malloc (datalen);
     fread (data, datalen, 1, f);
 
     *msize = 1 + 2 * sizeof (size_t) + chanlen + datalen;
@@ -476,8 +478,8 @@ void pubsubd_msg_send (const struct app_list_head *alh, const struct pubsub_msg
 {
     struct app_list_elm * ale = NULL;
 
-    char *buf;
-    size_t msize;
+    char *buf = NULL;
+    size_t msize = 0;
     pubsubd_msg_serialize (m, &buf, &msize);
 
     LIST_FOREACH(ale, alh, entries) {
@@ -504,8 +506,8 @@ void pubsubd_msg_print (const struct pubsub_msg *msg)
 void pubsubd_msg_recv (struct process *p, struct pubsub_msg *m)
 {
     // read the message from the process
-    size_t mlen;
-    char *buf;
+    size_t mlen = 0;
+    char *buf = NULL;
     srv_read_cb (p, &buf, &mlen, pubsubd_msg_read_cb);
 
     pubsubd_msg_unserialize (m, buf, mlen);
@@ -515,11 +517,52 @@ void pubsubd_msg_recv (struct process *p, struct pubsub_msg *m)
     }
 }
 
+#define PUBSUB_SUBSCRIBER_ACTION_STR_PUB    "pub"
+#define PUBSUB_SUBSCRIBER_ACTION_STR_SUB    "sub"
+#define PUBSUB_SUBSCRIBER_ACTION_STR_BOTH   "both"
+#define PUBSUB_SUBSCRIBER_ACTION_STR_QUIT   "quit"
+
+// enum app_list_elm_action {PUBSUB_QUIT = 1, PUBSUB_PUB, PUBSUB_SUB, PUBSUB_BOTH};
+
+char * pubsub_action_to_str (enum app_list_elm_action action)
+{
+    switch (action) {
+        case PUBSUB_PUB : return strdup (PUBSUB_SUBSCRIBER_ACTION_STR_PUB);
+        case PUBSUB_SUB : return strdup (PUBSUB_SUBSCRIBER_ACTION_STR_SUB);
+        case PUBSUB_BOTH : return strdup (PUBSUB_SUBSCRIBER_ACTION_STR_BOTH);
+        case PUBSUB_QUIT : return strdup (PUBSUB_SUBSCRIBER_ACTION_STR_QUIT);
+    }
+
+    return NULL;
+}
+
+void pubsub_connection (struct service *srv, struct process *p, enum app_list_elm_action action, const char *channame)
+{
+    char * straction = NULL;
+    straction = pubsub_action_to_str (action);
+
+    char line[BUFSIZ];
+    bzero (line, BUFSIZ);
+
+    // line fmt : pid index version action chan
+    // "quit" action is also possible (see pubsub_disconnect)
+    snprintf (line, BUFSIZ, "%d %d %d %s %s\n"
+            , p->pid, p->index, p->version
+            , straction
+            , channame);
+    line[BUFSIZ -1] = '\0'; // to be sure
+
+    // send the connection line in the $TMP/<service> pipe
+    app_srv_connection (srv, line, strlen (line));
+
+    if (straction != NULL)
+        free (straction);
+}
+
 void pubsub_msg_send (const struct service *s, struct process *p, const struct pubsub_msg * m)
 {
-
-    char *buf;
-    size_t msize;
+    char *buf = NULL;
+    size_t msize = 0;
     pubsubd_msg_serialize (m, &buf, &msize);
 
     app_write (p, buf, msize);
@@ -532,8 +575,8 @@ void pubsub_msg_send (const struct service *s, struct process *p, const struct p
 void pubsub_msg_recv (const struct service *s, struct process *p, struct pubsub_msg * m)
 {
     // read the message from the process
-    size_t mlen;
-    char *buf;
+    size_t mlen = 0;
+    char *buf = NULL;
     app_read_cb (p, &buf, &mlen, pubsubd_msg_read_cb);
 
     pubsubd_msg_unserialize (m, buf, mlen);
diff --git a/pingpong/pingpong.c b/pingpong/pingpong.c
index 276c216..ff58080 100644
--- a/pingpong/pingpong.c
+++ b/pingpong/pingpong.c
@@ -33,7 +33,7 @@ void main_loop (const struct service *srv)
 
         // about the message
         size_t msize = BUFSIZ;
-        char *buf;
+        char *buf = NULL;
 
         // printf ("before read\n");
         if ((ret = srv_read (&proc, &buf, &msize))) {
diff --git a/pubsub/pubsub-test-send.c b/pubsub/pubsub-test-send.c
new file mode 100644
index 0000000..b5a6ea5
--- /dev/null
+++ b/pubsub/pubsub-test-send.c
@@ -0,0 +1,59 @@
+#include "../lib/pubsubd.h"
+#include <stdlib.h>
+#include <pthread.h>
+
+#define MYMESSAGE "coucou"
+#define MYCHAN    "chan1"
+
+void
+ohshit(int rvalue, const char* str) {
+    fprintf (stderr, "\033[31merr: %s\033[00m\n", str);
+    exit (rvalue);
+}
+
+    int
+main(int argc, char* argv[])
+{
+    struct service srv;
+    bzero (&srv, sizeof (struct service));
+    srv_init (&srv, PUBSUB_SERVICE_NAME);
+    printf ("Writing on %s.\n", srv.spath);
+
+    struct process p;
+    bzero (&p, sizeof (struct process));
+    int index = 1;
+
+    if (app_create (&p, index)) // called by the application
+        ohshit (1, "app_create");
+
+    // send a message to warn the service we want to do something
+    // line : pid index version action chan
+    pubsub_connection (&srv, &p, PUBSUB_PUB, MYCHAN);
+
+    struct pubsub_msg m;
+    bzero (&m, sizeof (struct pubsub_msg));
+
+    // first message, "coucou"
+    m.type = PUBSUB_TYPE_INFO;
+    m.chan = malloc (strlen (MYCHAN));
+    m.chanlen = strlen (MYCHAN);
+    m.data = malloc (strlen (MYMESSAGE));
+    m.datalen = strlen (MYMESSAGE);
+    pubsub_msg_send (&srv, &p, &m);
+
+    // second message, to disconnect from the server
+    m.type = PUBSUB_TYPE_DISCONNECT;
+    pubsub_msg_send (&srv, &p, &m);
+
+    // free everything
+
+    pubsubd_msg_free (&m);
+
+    // the application will shut down, and remove the application named pipes
+    if (app_destroy (&p))
+        ohshit (1, "app_destroy");
+
+    srv_process_free (&p);
+
+    return EXIT_SUCCESS;
+}
diff --git a/pubsub/pubsubd.c b/pubsub/pubsubd.c
index d4fb904..f982f5e 100644
--- a/pubsub/pubsubd.c
+++ b/pubsub/pubsubd.c
@@ -75,7 +75,7 @@ main(int argc, char* argv[])
         // for each new process
         struct app_list_elm ale;
         bzero (&ale, sizeof (struct app_list_elm));
-        struct channel *chan;
+        struct channel *chan = NULL;
         pubsubd_get_new_process (&srv, &ale, &chans, &chan);
         pubsubd_channels_print (&chans);
 
@@ -92,13 +92,13 @@ main(int argc, char* argv[])
         }
 
         // TODO thread to handle multiple clients at a time
-        struct worker_params *wp;
+        struct worker_params *wp = NULL;
         wp = malloc (sizeof (struct worker_params));
         wp->ale = pubsubd_app_list_elm_copy (&ale);
         wp->chans = &chans;
         wp->chan = chan;
 
-        pthread_t thr;
+        pthread_t thr = 0;
 
         pthread_create (&thr, NULL, pubsubd_worker_thread, wp);
         pthread_detach (thr);