making GNUNET_SCHEDULER_cancel() perform in O(1) instead of O(n) to help or even fully address #3247

34 files changed, 218 insertions, 218 deletions

diff --git a/src/fs/fs_api.c b/src/fs/fs_api.c
index 302020d7d3..6c534ff322 100644
--- a/src/fs/fs_api.c
+++ b/src/fs/fs_api.c
@@ -131,7 +131,7 @@ process_job_queue (void *cls,
   int num_downloads_change;
   int block_limit_hit;
 
-  h->queue_job = GNUNET_SCHEDULER_NO_TASK;
+  h->queue_job = NULL;
   /* restart_at will be set to the time when it makes sense to
      re-evaluate the job queue (unless, of course, jobs complete
      or are added, then we'll be triggered immediately */
@@ -336,7 +336,7 @@ GNUNET_FS_queue_ (struct GNUNET_FS_Handle *h,
   qe->priority = priority;
   GNUNET_CONTAINER_DLL_insert_after (h->pending_head, h->pending_tail,
                                      h->pending_tail, qe);
-  if (h->queue_job != GNUNET_SCHEDULER_NO_TASK)
+  if (h->queue_job != NULL)
     GNUNET_SCHEDULER_cancel (h->queue_job);
   h->queue_job = GNUNET_SCHEDULER_add_now (&process_job_queue, h);
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
@@ -364,7 +364,7 @@ GNUNET_FS_dequeue_ (struct GNUNET_FS_QueueEntry *qe)
     stop_job (qe);
   GNUNET_CONTAINER_DLL_remove (h->pending_head, h->pending_tail, qe);
   GNUNET_free (qe);
-  if (h->queue_job != GNUNET_SCHEDULER_NO_TASK)
+  if (h->queue_job != NULL)
     GNUNET_SCHEDULER_cancel (h->queue_job);
   h->queue_job = GNUNET_SCHEDULER_add_now (&process_job_queue, h);
 }
@@ -1619,7 +1619,7 @@ deserialize_publish_file (void *cls,
   /* re-start publishing (if needed)... */
   if (GNUNET_YES != pc->all_done)
   {
-    GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == pc->upload_task);
+    GNUNET_assert (NULL == pc->upload_task);
     pc->upload_task =
         GNUNET_SCHEDULER_add_with_priority
         (GNUNET_SCHEDULER_PRIORITY_BACKGROUND,
@@ -2140,7 +2140,7 @@ GNUNET_FS_search_sync_ (struct GNUNET_FS_SearchContext *sc)
   GNUNET_assert ((GNUNET_YES == GNUNET_FS_uri_test_ksk (sc->uri)) ||
                  (GNUNET_YES == GNUNET_FS_uri_test_sks (sc->uri)));
   uris = GNUNET_FS_uri_to_string (sc->uri);
-  in_pause = (sc->task != GNUNET_SCHEDULER_NO_TASK) ? 'r' : '\0';
+  in_pause = (sc->task != NULL) ? 'r' : '\0';
   if ((GNUNET_OK != GNUNET_BIO_write_string (wh, uris)) ||
       (GNUNET_OK != write_start_time (wh, sc->start_time)) ||
       (GNUNET_OK != GNUNET_BIO_write_string (wh, sc->emsg)) ||
@@ -3130,7 +3130,7 @@ GNUNET_FS_stop (struct GNUNET_FS_Handle *h)
 {
   while (h->top_head != NULL)
     h->top_head->ssf (h->top_head->ssf_cls);
-  if (h->queue_job != GNUNET_SCHEDULER_NO_TASK)
+  if (h->queue_job != NULL)
     GNUNET_SCHEDULER_cancel (h->queue_job);
   GNUNET_free (h->client_name);
   GNUNET_free (h);
diff --git a/src/fs/fs_api.h b/src/fs/fs_api.h
index 157662a65b..5fbdef6c24 100644
--- a/src/fs/fs_api.h
+++ b/src/fs/fs_api.h
@@ -601,7 +601,7 @@ struct GNUNET_FS_SearchResult
    * complete on time (and that will need to be cancelled if we clean
    * up the search result before then).
    */
-  GNUNET_SCHEDULER_TaskIdentifier probe_cancel_task;
+  struct GNUNET_SCHEDULER_Task * probe_cancel_task;
 
   /**
    * When did the current probe become active?
@@ -1170,13 +1170,13 @@ struct GNUNET_FS_Handle
    * Task that processes the jobs in the running and pending queues
    * (and moves jobs around as needed).
    */
-  GNUNET_SCHEDULER_TaskIdentifier queue_job;
+  struct GNUNET_SCHEDULER_Task * queue_job;
 
   /**
    * Task we use to report periodically to the application that
    * certain search probes (from @e probes_head) are still running.
    */
-  GNUNET_SCHEDULER_TaskIdentifier probe_ping_task;
+  struct GNUNET_SCHEDULER_Task * probe_ping_task;
 
   /**
    * Average time we take for a single request to be satisfied.
@@ -1300,7 +1300,7 @@ struct GNUNET_FS_PublishContext
    * ID of the task performing the upload. NO_TASK if the upload has
    * completed.
    */
-  GNUNET_SCHEDULER_TaskIdentifier upload_task;
+  struct GNUNET_SCHEDULER_Task * upload_task;
 
   /**
    * Storage space to reserve for the operation.
@@ -1629,10 +1629,10 @@ struct GNUNET_FS_SearchContext
   /**
    * ID of a task that is using this struct and that must be cancelled
    * when the search is being stopped (if not
-   * #GNUNET_SCHEDULER_NO_TASK).  Used for the task that adds some
+   * #NULL).  Used for the task that adds some
    * artificial delay when trying to reconnect to the FS service.
    */
-  GNUNET_SCHEDULER_TaskIdentifier task;
+  struct GNUNET_SCHEDULER_Task * task;
 
   /**
    * How many of the entries in the search request
@@ -1961,12 +1961,12 @@ struct GNUNET_FS_DownloadContext
   /**
    * ID of a task that is using this struct and that must be cancelled
    * when the download is being stopped (if not
-   * #GNUNET_SCHEDULER_NO_TASK).  Used for the task that adds some
+   * #NULL).  Used for the task that adds some
    * artificial delay when trying to reconnect to the FS service or
    * the task processing incrementally the data on disk, or the
    * task requesting blocks, etc.
    */
-  GNUNET_SCHEDULER_TaskIdentifier task;
+  struct GNUNET_SCHEDULER_Task * task;
 
   /**
    * What is the first offset that we're interested
diff --git a/src/fs/fs_dirmetascan.c b/src/fs/fs_dirmetascan.c
index 83e436b168..2477aab4b9 100644
--- a/src/fs/fs_dirmetascan.c
+++ b/src/fs/fs_dirmetascan.c
@@ -80,7 +80,7 @@ struct GNUNET_FS_DirScanner
   /**
    * Task scheduled when we are done.
    */
-  GNUNET_SCHEDULER_TaskIdentifier stop_task;
+  struct GNUNET_SCHEDULER_Task * stop_task;
 
   /**
    * Arguments for helper.
@@ -106,7 +106,7 @@ GNUNET_FS_directory_scan_abort (struct GNUNET_FS_DirScanner *ds)
   /* free resources */
   if (NULL != ds->toplevel)
     GNUNET_FS_share_tree_free (ds->toplevel);
-  if (GNUNET_SCHEDULER_NO_TASK != ds->stop_task)
+  if (NULL != ds->stop_task)
     GNUNET_SCHEDULER_cancel (ds->stop_task);
   GNUNET_free_non_null (ds->ex_arg);
   GNUNET_free (ds->filename_expanded);
@@ -230,7 +230,7 @@ finish_scan (void *cls,
 {
   struct GNUNET_FS_DirScanner *ds = cls;
 
-  ds->stop_task = GNUNET_SCHEDULER_NO_TASK;
+  ds->stop_task = NULL;
   if (NULL != ds->helper)
   {
     GNUNET_HELPER_stop (ds->helper, GNUNET_NO);
@@ -427,7 +427,7 @@ helper_died_cb (void *cls)
   struct GNUNET_FS_DirScanner *ds = cls;
 
   ds->helper = NULL;
-  if (GNUNET_SCHEDULER_NO_TASK != ds->stop_task)
+  if (NULL != ds->stop_task)
     return; /* normal death, was finished */
   ds->progress_callback (ds->progress_callback_cls,
 			 NULL, GNUNET_SYSERR,
diff --git a/src/fs/fs_download.c b/src/fs/fs_download.c
index 348a0bc173..3a6072d8ba 100644
--- a/src/fs/fs_download.c
+++ b/src/fs/fs_download.c
@@ -393,10 +393,10 @@ check_completed (struct GNUNET_FS_DownloadContext *dc)
     GNUNET_FS_dequeue_ (dc->job_queue);
     dc->job_queue = NULL;
   }
-  if (GNUNET_SCHEDULER_NO_TASK != dc->task)
+  if (NULL != dc->task)
   {
     GNUNET_SCHEDULER_cancel (dc->task);
-    dc->task = GNUNET_SCHEDULER_NO_TASK;
+    dc->task = NULL;
   }
   if (NULL != dc->rfh)
   {
@@ -1380,7 +1380,7 @@ do_reconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   struct GNUNET_FS_DownloadContext *dc = cls;
   struct GNUNET_CLIENT_Connection *client;
 
-  dc->task = GNUNET_SCHEDULER_NO_TASK;
+  dc->task = NULL;
   client = GNUNET_CLIENT_connect ("fs", dc->h->cfg);
   if (NULL == client)
   {
@@ -1633,10 +1633,10 @@ reconstruct_cont (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   struct GNUNET_FS_DownloadContext *dc = cls;
 
   /* clean up state from tree encoder */
-  if (dc->task != GNUNET_SCHEDULER_NO_TASK)
+  if (dc->task != NULL)
   {
     GNUNET_SCHEDULER_cancel (dc->task);
-    dc->task = GNUNET_SCHEDULER_NO_TASK;
+    dc->task = NULL;
   }
   if (NULL != dc->rfh)
   {
@@ -1662,7 +1662,7 @@ get_next_block (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   struct GNUNET_FS_DownloadContext *dc = cls;
 
-  dc->task = GNUNET_SCHEDULER_NO_TASK;
+  dc->task = NULL;
   GNUNET_FS_tree_encoder_next (dc->te);
 }
 
@@ -1866,7 +1866,7 @@ GNUNET_FS_download_start_task_ (void *cls,
   struct GNUNET_DISK_FileHandle *fh;
 
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Start task running...\n");
-  dc->task = GNUNET_SCHEDULER_NO_TASK;
+  dc->task = NULL;
   if (0 == dc->length)
   {
     /* no bytes required! */
@@ -2028,10 +2028,10 @@ GNUNET_FS_download_signal_suspend_ (void *cls)
   if (NULL != dc->parent)
     GNUNET_CONTAINER_DLL_remove (dc->parent->child_head, dc->parent->child_tail,
                                  dc);
-  if (GNUNET_SCHEDULER_NO_TASK != dc->task)
+  if (NULL != dc->task)
   {
     GNUNET_SCHEDULER_cancel (dc->task);
-    dc->task = GNUNET_SCHEDULER_NO_TASK;
+    dc->task = NULL;
   }
   pi.status = GNUNET_FS_STATUS_DOWNLOAD_SUSPEND;
   GNUNET_FS_download_make_status_ (&pi, dc);
@@ -2336,10 +2336,10 @@ GNUNET_FS_download_stop (struct GNUNET_FS_DownloadContext *dc, int do_delete)
 
   if (NULL != dc->top)
     GNUNET_FS_end_top (dc->h, dc->top);
-  if (GNUNET_SCHEDULER_NO_TASK != dc->task)
+  if (NULL != dc->task)
   {
     GNUNET_SCHEDULER_cancel (dc->task);
-    dc->task = GNUNET_SCHEDULER_NO_TASK;
+    dc->task = NULL;
   }
   search_was_null = (NULL == dc->search);
   if (NULL != dc->search)
diff --git a/src/fs/fs_list_indexed.c b/src/fs/fs_list_indexed.c
index 7a891155e3..8c25587452 100644
--- a/src/fs/fs_list_indexed.c
+++ b/src/fs/fs_list_indexed.c
@@ -59,7 +59,7 @@ struct GNUNET_FS_GetIndexedContext
   /**
    * Continuation to trigger at the end.
    */
-  GNUNET_SCHEDULER_Task cont;
+  GNUNET_SCHEDULER_TaskCallback cont;
 
   /**
    * Closure for cont.
diff --git a/src/fs/fs_publish.c b/src/fs/fs_publish.c
index a8a9a220f1..175e453c64 100644
--- a/src/fs/fs_publish.c
+++ b/src/fs/fs_publish.c
@@ -97,7 +97,7 @@ publish_cleanup (struct GNUNET_FS_PublishContext *pc)
     GNUNET_CLIENT_disconnect (pc->client);
     pc->client = NULL;
   }
-  GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == pc->upload_task);
+  GNUNET_assert (NULL == pc->upload_task);
   GNUNET_free (pc);
 }
 
@@ -138,7 +138,7 @@ ds_put_cont (void *cls, int success,
       GNUNET_FS_unindex_start (pc->h, pc->fi_pos->filename, NULL);
     }
   }
-  GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == pc->upload_task);
+  GNUNET_assert (NULL == pc->upload_task);
   pc->upload_task =
       GNUNET_SCHEDULER_add_with_priority (GNUNET_SCHEDULER_PRIORITY_BACKGROUND,
                                           &GNUNET_FS_publish_main_, pc);
@@ -316,7 +316,7 @@ publish_kblocks_cont (void *cls,
     signal_publish_error (p, pc, emsg);
     GNUNET_FS_file_information_sync_ (p);
     GNUNET_FS_publish_sync_ (pc);
-    GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == pc->upload_task);
+    GNUNET_assert (NULL == pc->upload_task);
     pc->upload_task =
       GNUNET_SCHEDULER_add_with_priority
       (GNUNET_SCHEDULER_PRIORITY_BACKGROUND,
@@ -334,7 +334,7 @@ publish_kblocks_cont (void *cls,
   else
     pc->fi_pos = p->dir;
   GNUNET_FS_publish_sync_ (pc);
-  GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == pc->upload_task);
+  GNUNET_assert (NULL == pc->upload_task);
   pc->upload_task =
       GNUNET_SCHEDULER_add_with_priority (GNUNET_SCHEDULER_PRIORITY_BACKGROUND,
                                           &GNUNET_FS_publish_main_, pc);
@@ -449,7 +449,7 @@ encode_cont (void *cls,
     p->client_info = GNUNET_FS_publish_make_status_ (&pi, pc, p, flen);
   }
   /* continue with main */  /* continue with main */
-  GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == pc->upload_task);
+  GNUNET_assert (NULL == pc->upload_task);
   pc->upload_task =
       GNUNET_SCHEDULER_add_with_priority (GNUNET_SCHEDULER_PRIORITY_BACKGROUND,
                                           &GNUNET_FS_publish_main_, pc);
@@ -487,7 +487,7 @@ block_proc (void *cls,
   if (NULL == pc->dsh)
   {
     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Waiting for datastore connection\n");
-    GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == pc->upload_task);
+    GNUNET_assert (NULL == pc->upload_task);
     pc->upload_task =
         GNUNET_SCHEDULER_add_with_priority
         (GNUNET_SCHEDULER_PRIORITY_BACKGROUND, &GNUNET_FS_publish_main_, pc);
@@ -947,7 +947,7 @@ GNUNET_FS_publish_main_ (void *cls,
   struct GNUNET_FS_FileInformation *p;
   char *fn;
 
-  pc->upload_task = GNUNET_SCHEDULER_NO_TASK;
+  pc->upload_task = NULL;
   p = pc->fi_pos;
   if (NULL == p)
   {
@@ -1234,10 +1234,10 @@ GNUNET_FS_publish_signal_suspend_ (void *cls)
 {
   struct GNUNET_FS_PublishContext *pc = cls;
 
-  if (GNUNET_SCHEDULER_NO_TASK != pc->upload_task)
+  if (NULL != pc->upload_task)
   {
     GNUNET_SCHEDULER_cancel (pc->upload_task);
-    pc->upload_task = GNUNET_SCHEDULER_NO_TASK;
+    pc->upload_task = NULL;
   }
   pc->skip_next_fi_callback = GNUNET_YES;
   GNUNET_FS_file_information_inspect (pc->fi, &fip_signal_suspend, pc);
@@ -1275,7 +1275,7 @@ finish_reserve (void *cls, int success,
     return;
   }
   pc->rid = success;
-  GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == pc->upload_task);
+  GNUNET_assert (NULL == pc->upload_task);
   pc->upload_task =
       GNUNET_SCHEDULER_add_with_priority (GNUNET_SCHEDULER_PRIORITY_BACKGROUND,
                                           &GNUNET_FS_publish_main_, pc);
@@ -1373,7 +1373,7 @@ GNUNET_FS_publish_start (struct GNUNET_FS_Handle *h,
   }
   else
   {
-    GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == ret->upload_task);
+    GNUNET_assert (NULL == ret->upload_task);
     ret->upload_task =
         GNUNET_SCHEDULER_add_with_priority
         (GNUNET_SCHEDULER_PRIORITY_BACKGROUND, &GNUNET_FS_publish_main_, ret);
@@ -1462,10 +1462,10 @@ GNUNET_FS_publish_stop (struct GNUNET_FS_PublishContext *pc)
     GNUNET_FS_publish_sks_cancel (pc->sks_pc);
     pc->sks_pc = NULL;
   }
-  if (GNUNET_SCHEDULER_NO_TASK != pc->upload_task)
+  if (NULL != pc->upload_task)
   {
     GNUNET_SCHEDULER_cancel (pc->upload_task);
-    pc->upload_task = GNUNET_SCHEDULER_NO_TASK;
+    pc->upload_task = NULL;
   }
   pc->skip_next_fi_callback = GNUNET_YES;
   GNUNET_FS_file_information_inspect (pc->fi, &fip_signal_stop, pc);
diff --git a/src/fs/fs_publish_ksk.c b/src/fs/fs_publish_ksk.c
index 67157f408b..436bac6334 100644
--- a/src/fs/fs_publish_ksk.c
+++ b/src/fs/fs_publish_ksk.c
@@ -74,7 +74,7 @@ struct GNUNET_FS_PublishKskContext
   /**
    * Current task.
    */
-  GNUNET_SCHEDULER_TaskIdentifier ksk_task;
+  struct GNUNET_SCHEDULER_Task * ksk_task;
 
   /**
    * Function to call once we're done.
@@ -156,7 +156,7 @@ publish_ksk_cont (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   struct GNUNET_FS_PublishKskContext *pkc = cls;
   const char *keyword;
 
-  pkc->ksk_task = GNUNET_SCHEDULER_NO_TASK;
+  pkc->ksk_task = NULL;
   if ( (pkc->i == pkc->ksk_uri->data.ksk.keywordCount) ||
        (NULL == pkc->dsh) )
   {
@@ -236,10 +236,10 @@ GNUNET_FS_publish_ksk (struct GNUNET_FS_Handle *h,
 void
 GNUNET_FS_publish_ksk_cancel (struct GNUNET_FS_PublishKskContext *pkc)
 {
-  if (GNUNET_SCHEDULER_NO_TASK != pkc->ksk_task)
+  if (NULL != pkc->ksk_task)
   {
     GNUNET_SCHEDULER_cancel (pkc->ksk_task);
-    pkc->ksk_task = GNUNET_SCHEDULER_NO_TASK;
+    pkc->ksk_task = NULL;
   }
   if (NULL != pkc->uc)
   {
diff --git a/src/fs/fs_publish_ublock.c b/src/fs/fs_publish_ublock.c
index 4399b8c8ec..1cba7a4fcc 100644
--- a/src/fs/fs_publish_ublock.c
+++ b/src/fs/fs_publish_ublock.c
@@ -112,7 +112,7 @@ struct GNUNET_FS_PublishUblockContext
   /**
    * Task to run continuation asynchronously.
    */
-  GNUNET_SCHEDULER_TaskIdentifier task;
+  struct GNUNET_SCHEDULER_Task * task;
 
 };
 
@@ -155,7 +155,7 @@ run_cont (void *cls,
 {
   struct GNUNET_FS_PublishUblockContext *uc = cls;
 
-  uc->task = GNUNET_SCHEDULER_NO_TASK;
+  uc->task = NULL;
   uc->cont (uc->cont_cls, NULL);
   GNUNET_free (uc);
 }
@@ -316,7 +316,7 @@ GNUNET_FS_publish_ublock_cancel_ (struct GNUNET_FS_PublishUblockContext *uc)
 {
   if (NULL != uc->qre)
     GNUNET_DATASTORE_cancel (uc->qre);
-  if (GNUNET_SCHEDULER_NO_TASK != uc->task)
+  if (NULL != uc->task)
     GNUNET_SCHEDULER_cancel (uc->task);
   GNUNET_free (uc);
 }
diff --git a/src/fs/fs_search.c b/src/fs/fs_search.c
index c85d6d3df6..8f640009a6 100644
--- a/src/fs/fs_search.c
+++ b/src/fs/fs_search.c
@@ -223,7 +223,7 @@ probe_failure_handler (void *cls,
 {
   struct GNUNET_FS_SearchResult *sr = cls;
 
-  sr->probe_cancel_task = GNUNET_SCHEDULER_NO_TASK;
+  sr->probe_cancel_task = NULL;
   sr->availability_trials++;
   GNUNET_FS_download_stop (sr->probe_ctx, GNUNET_YES);
   sr->probe_ctx = NULL;
@@ -249,7 +249,7 @@ probe_success_handler (void *cls,
 {
   struct GNUNET_FS_SearchResult *sr = cls;
 
-  sr->probe_cancel_task = GNUNET_SCHEDULER_NO_TASK;
+  sr->probe_cancel_task = NULL;
   sr->availability_trials++;
   sr->availability_success++;
   GNUNET_FS_download_stop (sr->probe_ctx, GNUNET_YES);
@@ -303,34 +303,34 @@ GNUNET_FS_search_probe_progress_ (void *cls,
     /* ignore */
     break;
   case GNUNET_FS_STATUS_DOWNLOAD_ERROR:
-    if (GNUNET_SCHEDULER_NO_TASK != sr->probe_cancel_task)
+    if (NULL != sr->probe_cancel_task)
     {
       GNUNET_SCHEDULER_cancel (sr->probe_cancel_task);
-      sr->probe_cancel_task = GNUNET_SCHEDULER_NO_TASK;
+      sr->probe_cancel_task = NULL;
     }
     sr->probe_cancel_task =
         GNUNET_SCHEDULER_add_delayed (sr->remaining_probe_time,
                                       &probe_failure_handler, sr);
     break;
   case GNUNET_FS_STATUS_DOWNLOAD_COMPLETED:
-    if (GNUNET_SCHEDULER_NO_TASK != sr->probe_cancel_task)
+    if (NULL != sr->probe_cancel_task)
     {
       GNUNET_SCHEDULER_cancel (sr->probe_cancel_task);
-      sr->probe_cancel_task = GNUNET_SCHEDULER_NO_TASK;
+      sr->probe_cancel_task = NULL;
     }
     sr->probe_cancel_task =
         GNUNET_SCHEDULER_add_now (&probe_success_handler, sr);
     break;
   case GNUNET_FS_STATUS_DOWNLOAD_STOPPED:
-    if (GNUNET_SCHEDULER_NO_TASK != sr->probe_cancel_task)
+    if (NULL != sr->probe_cancel_task)
     {
       GNUNET_SCHEDULER_cancel (sr->probe_cancel_task);
-      sr->probe_cancel_task = GNUNET_SCHEDULER_NO_TASK;
+      sr->probe_cancel_task = NULL;
     }
     sr = NULL;
     break;
   case GNUNET_FS_STATUS_DOWNLOAD_ACTIVE:
-    if (GNUNET_SCHEDULER_NO_TASK == sr->probe_cancel_task)
+    if (NULL == sr->probe_cancel_task)
     {
       sr->probe_active_time = GNUNET_TIME_absolute_get ();
       sr->probe_cancel_task =
@@ -339,10 +339,10 @@ GNUNET_FS_search_probe_progress_ (void *cls,
     }
     break;
   case GNUNET_FS_STATUS_DOWNLOAD_INACTIVE:
-    if (GNUNET_SCHEDULER_NO_TASK != sr->probe_cancel_task)
+    if (NULL != sr->probe_cancel_task)
     {
       GNUNET_SCHEDULER_cancel (sr->probe_cancel_task);
-      sr->probe_cancel_task = GNUNET_SCHEDULER_NO_TASK;
+      sr->probe_cancel_task = NULL;
     }
     dur = GNUNET_TIME_absolute_get_duration (sr->probe_active_time);
     sr->remaining_probe_time =
@@ -396,7 +396,7 @@ start_probe_ping_task (struct GNUNET_FS_SearchResult *sr)
   GNUNET_CONTAINER_DLL_insert (h->probes_head,
                                h->probes_tail,
                                sr);
-  if (GNUNET_SCHEDULER_NO_TASK == h->probe_ping_task)
+  if (NULL == h->probe_ping_task)
     h->probe_ping_task
       = GNUNET_SCHEDULER_add_now (&probe_ping_task_cb,
                                   h);
@@ -419,7 +419,7 @@ GNUNET_FS_stop_probe_ping_task_ (struct GNUNET_FS_SearchResult *sr)
   if (NULL == h->probes_head)
   {
     GNUNET_SCHEDULER_cancel (h->probe_ping_task);
-    h->probe_ping_task = GNUNET_SCHEDULER_NO_TASK;
+    h->probe_ping_task = NULL;
   }
 }
 
@@ -520,10 +520,10 @@ GNUNET_FS_search_stop_probe_ (struct GNUNET_FS_SearchResult *sr)
     sr->probe_ctx = NULL;
     GNUNET_FS_stop_probe_ping_task_ (sr);
   }
-  if (GNUNET_SCHEDULER_NO_TASK != sr->probe_cancel_task)
+  if (NULL != sr->probe_cancel_task)
   {
     GNUNET_SCHEDULER_cancel (sr->probe_cancel_task);
-    sr->probe_cancel_task = GNUNET_SCHEDULER_NO_TASK;
+    sr->probe_cancel_task = NULL;
   }
 }
 
@@ -1253,7 +1253,7 @@ do_reconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   struct GNUNET_FS_SearchContext *sc = cls;
   struct GNUNET_CLIENT_Connection *client;
 
-  sc->task = GNUNET_SCHEDULER_NO_TASK;
+  sc->task = NULL;
   client = GNUNET_CLIENT_connect ("fs", sc->h->cfg);
   if (NULL == client)
   {
@@ -1446,10 +1446,10 @@ search_result_freeze_probes (void *cls,
     sr->probe_ctx = NULL;
     GNUNET_FS_stop_probe_ping_task_ (sr);
   }
-  if (GNUNET_SCHEDULER_NO_TASK != sr->probe_cancel_task)
+  if (NULL != sr->probe_cancel_task)
   {
     GNUNET_SCHEDULER_cancel (sr->probe_cancel_task);
-    sr->probe_cancel_task = GNUNET_SCHEDULER_NO_TASK;
+    sr->probe_cancel_task = NULL;
   }
   if (NULL != sr->update_search)
     GNUNET_FS_search_pause (sr->update_search);
@@ -1545,10 +1545,10 @@ GNUNET_FS_search_signal_suspend_ (void *cls)
   pi.status = GNUNET_FS_STATUS_SEARCH_SUSPEND;
   sc->client_info = GNUNET_FS_search_make_status_ (&pi, sc->h, sc);
   GNUNET_break (NULL == sc->client_info);
-  if (sc->task != GNUNET_SCHEDULER_NO_TASK)
+  if (sc->task != NULL)
   {
     GNUNET_SCHEDULER_cancel (sc->task);
-    sc->task = GNUNET_SCHEDULER_NO_TASK;
+    sc->task = NULL;
   }
   if (NULL != sc->client)
   {
@@ -1609,10 +1609,10 @@ GNUNET_FS_search_pause (struct GNUNET_FS_SearchContext *sc)
 {
   struct GNUNET_FS_ProgressInfo pi;
 
-  if (GNUNET_SCHEDULER_NO_TASK != sc->task)
+  if (NULL != sc->task)
   {
     GNUNET_SCHEDULER_cancel (sc->task);
-    sc->task = GNUNET_SCHEDULER_NO_TASK;
+    sc->task = NULL;
   }
   if (NULL != sc->client)
     GNUNET_CLIENT_disconnect (sc->client);
@@ -1636,7 +1636,7 @@ GNUNET_FS_search_continue (struct GNUNET_FS_SearchContext *sc)
   struct GNUNET_FS_ProgressInfo pi;
 
   GNUNET_assert (NULL == sc->client);
-  GNUNET_assert (GNUNET_SCHEDULER_NO_TASK == sc->task);
+  GNUNET_assert (NULL == sc->task);
   do_reconnect (sc, NULL);
   GNUNET_FS_search_sync_ (sc);
   pi.status = GNUNET_FS_STATUS_SEARCH_CONTINUED;
@@ -1721,7 +1721,7 @@ search_result_free (void *cls,
     GNUNET_assert (NULL == sr->update_search);
   }
   GNUNET_break (NULL == sr->probe_ctx);
-  GNUNET_break (GNUNET_SCHEDULER_NO_TASK == sr->probe_cancel_task);
+  GNUNET_break (NULL == sr->probe_cancel_task);
   GNUNET_break (NULL == sr->client_info);
   GNUNET_free_non_null (sr->serialization);
   GNUNET_FS_uri_destroy (sr->uri);
@@ -1766,7 +1766,7 @@ GNUNET_FS_search_stop (struct GNUNET_FS_SearchContext *sc)
   pi.status = GNUNET_FS_STATUS_SEARCH_STOPPED;
   sc->client_info = GNUNET_FS_search_make_status_ (&pi, sc->h, sc);
   GNUNET_break (NULL == sc->client_info);
-  if (GNUNET_SCHEDULER_NO_TASK != sc->task)
+  if (NULL != sc->task)
     GNUNET_SCHEDULER_cancel (sc->task);
   if (NULL != sc->client)
     GNUNET_CLIENT_disconnect (sc->client);
diff --git a/src/fs/fs_test_lib.c b/src/fs/fs_test_lib.c
index 1e098bd60e..589f979d63 100644
--- a/src/fs/fs_test_lib.c
+++ b/src/fs/fs_test_lib.c
@@ -63,7 +63,7 @@ struct TestPublishOperation
   /**
    * Task to abort publishing (timeout).
    */
-  GNUNET_SCHEDULER_TaskIdentifier publish_timeout_task;
+  struct GNUNET_SCHEDULER_Task * publish_timeout_task;
 
   /**
    * Seed for file generation.
@@ -131,7 +131,7 @@ struct TestDownloadOperation
   /**
    * Function to call when download is done.
    */
-  GNUNET_SCHEDULER_Task download_cont;
+  GNUNET_SCHEDULER_TaskCallback download_cont;
 
   /**
    * Closure for download_cont.
@@ -146,7 +146,7 @@ struct TestDownloadOperation
   /**
    * Task to abort downloading (timeout).
    */
-  GNUNET_SCHEDULER_TaskIdentifier download_timeout_task;
+  struct GNUNET_SCHEDULER_Task * download_timeout_task;
 
   /**
    * Context for current download operation.
@@ -215,7 +215,7 @@ publish_timeout (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   struct TestPublishOperation *po = cls;
 
-  po->publish_timeout_task = GNUNET_SCHEDULER_NO_TASK;
+  po->publish_timeout_task = NULL;
   GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
               "Timeout while trying to publish data\n");
   GNUNET_TESTBED_operation_done (po->fs_op);
@@ -242,7 +242,7 @@ publish_progress_cb (void *cls, const struct GNUNET_FS_ProgressInfo *info)
   {
   case GNUNET_FS_STATUS_PUBLISH_COMPLETED:
     GNUNET_SCHEDULER_cancel (po->publish_timeout_task);
-    po->publish_timeout_task = GNUNET_SCHEDULER_NO_TASK;
+    po->publish_timeout_task = NULL;
     po->publish_uri =
         GNUNET_FS_uri_dup (info->value.publish.specifics.completed.chk_uri);
     GNUNET_SCHEDULER_add_continuation (&report_uri, po,
@@ -489,7 +489,7 @@ download_timeout (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 
   GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
               "Timeout while trying to download file\n");
-  dop->download_timeout_task = GNUNET_SCHEDULER_NO_TASK;
+  dop->download_timeout_task = NULL;
   GNUNET_FS_download_stop (dop->download_context, GNUNET_YES);
   GNUNET_SCHEDULER_add_continuation (dop->download_cont,
                                      dop->download_cont_cls,
@@ -543,7 +543,7 @@ download_progress_cb (void *cls, const struct GNUNET_FS_ProgressInfo *info)
     break;
   case GNUNET_FS_STATUS_DOWNLOAD_COMPLETED:
     GNUNET_SCHEDULER_cancel (dop->download_timeout_task);
-    dop->download_timeout_task = GNUNET_SCHEDULER_NO_TASK;
+    dop->download_timeout_task = NULL;
     GNUNET_SCHEDULER_add_continuation (&report_success, dop,
                                        GNUNET_SCHEDULER_REASON_PREREQ_DONE);
     break;
@@ -627,7 +627,7 @@ GNUNET_FS_TEST_download (struct GNUNET_TESTBED_Peer *peer,
                          struct GNUNET_TIME_Relative timeout,
                          uint32_t anonymity, uint32_t seed,
                          const struct GNUNET_FS_Uri *uri, unsigned int verbose,
-                         GNUNET_SCHEDULER_Task cont, void *cont_cls)
+                         GNUNET_SCHEDULER_TaskCallback cont, void *cont_cls)
 {
   struct TestDownloadOperation *dop;
 
diff --git a/src/fs/fs_test_lib.h b/src/fs/fs_test_lib.h
index 679e0745c2..112ff38930 100644
--- a/src/fs/fs_test_lib.h
+++ b/src/fs/fs_test_lib.h
@@ -89,7 +89,7 @@ GNUNET_FS_TEST_download (struct GNUNET_TESTBED_Peer *peer,
                          struct GNUNET_TIME_Relative timeout,
                          uint32_t anonymity, uint32_t seed,
                          const struct GNUNET_FS_Uri *uri, unsigned int verbose,
-                         GNUNET_SCHEDULER_Task cont, void *cont_cls);
+                         GNUNET_SCHEDULER_TaskCallback cont, void *cont_cls);
 
 
 
diff --git a/src/fs/fs_tree.c b/src/fs/fs_tree.c
index 5dc39e4e61..715ecddb15 100644
--- a/src/fs/fs_tree.c
+++ b/src/fs/fs_tree.c
@@ -63,7 +63,7 @@ struct GNUNET_FS_TreeEncoder
   /**
    * Function to call once we're done with processing.
    */
-  GNUNET_SCHEDULER_Task cont;
+  GNUNET_SCHEDULER_TaskCallback cont;
 
   /**
    * Set to an error message (if we had an error).
@@ -272,7 +272,7 @@ GNUNET_FS_tree_encoder_create (struct GNUNET_FS_Handle *h, uint64_t size,
 			       GNUNET_FS_DataReader reader,
                                GNUNET_FS_TreeBlockProcessor proc,
                                GNUNET_FS_TreeProgressCallback progress,
-                               GNUNET_SCHEDULER_Task cont)
+                               GNUNET_SCHEDULER_TaskCallback cont)
 {
   struct GNUNET_FS_TreeEncoder *te;
 
diff --git a/src/fs/fs_tree.h b/src/fs/fs_tree.h
index cd25a6dd14..2aef80b858 100644
--- a/src/fs/fs_tree.h
+++ b/src/fs/fs_tree.h
@@ -142,7 +142,7 @@ GNUNET_FS_tree_encoder_create (struct GNUNET_FS_Handle *h, uint64_t size,
                                void *cls, GNUNET_FS_DataReader reader,
                                GNUNET_FS_TreeBlockProcessor proc,
                                GNUNET_FS_TreeProgressCallback progress,
-                               GNUNET_SCHEDULER_Task cont);
+                               GNUNET_SCHEDULER_TaskCallback cont);
 
 
 /**
diff --git a/src/fs/gnunet-auto-share.c b/src/fs/gnunet-auto-share.c
index 32725f66f0..c3b19b9edb 100644
--- a/src/fs/gnunet-auto-share.c
+++ b/src/fs/gnunet-auto-share.c
@@ -97,12 +97,12 @@ static int do_disable_creation_time;
 /**
  * Handle for the 'shutdown' task.
  */
-static GNUNET_SCHEDULER_TaskIdentifier kill_task;
+static struct GNUNET_SCHEDULER_Task * kill_task;
 
 /**
  * Handle for the main task that does scanning and working.
  */
-static GNUNET_SCHEDULER_TaskIdentifier run_task;
+static struct GNUNET_SCHEDULER_Task * run_task;
 
 /**
  * Anonymity level option to use for publishing.
@@ -322,17 +322,17 @@ save_state ()
 static void
 do_stop_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  kill_task = GNUNET_SCHEDULER_NO_TASK;
+  kill_task = NULL;
   do_shutdown = GNUNET_YES;
   if (NULL != publish_proc)
   {
     GNUNET_OS_process_kill (publish_proc, SIGKILL);
     return;
   }
-  if (GNUNET_SCHEDULER_NO_TASK != run_task)
+  if (NULL != run_task)
   {
     GNUNET_SCHEDULER_cancel (run_task);
-    run_task = GNUNET_SCHEDULER_NO_TASK;
+    run_task = NULL;
   }
 }
 
@@ -363,7 +363,7 @@ maint_child_death (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   const struct GNUNET_DISK_FileHandle *pr;
 
 
-  run_task = GNUNET_SCHEDULER_NO_TASK;
+  run_task = NULL;
   pr = GNUNET_DISK_pipe_handle (sigpipe, GNUNET_DISK_PIPE_END_READ);
   if (0 == (tc->reason & GNUNET_SCHEDULER_REASON_READ_READY))
   {
@@ -457,7 +457,7 @@ work (void *cls,
   const struct GNUNET_DISK_FileHandle *pr;
   int argc;
 
-  run_task = GNUNET_SCHEDULER_NO_TASK;
+  run_task = NULL;
   wi = work_head;
   GNUNET_CONTAINER_DLL_remove (work_head,
 			       work_tail,
@@ -629,7 +629,7 @@ add_file (void *cls,
 static void
 scan (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  run_task = GNUNET_SCHEDULER_NO_TASK;
+  run_task = NULL;
   start_time = GNUNET_TIME_absolute_get ();
   (void) GNUNET_DISK_directory_scan (dir_name,
 				     &add_file,
diff --git a/src/fs/gnunet-daemon-fsprofiler.c b/src/fs/gnunet-daemon-fsprofiler.c
index 1549972a1c..9c4f28351c 100644
--- a/src/fs/gnunet-daemon-fsprofiler.c
+++ b/src/fs/gnunet-daemon-fsprofiler.c
@@ -69,12 +69,12 @@ struct Pattern
   /**
    * Task to run the operation.
    */
-  GNUNET_SCHEDULER_TaskIdentifier task;
+  struct GNUNET_SCHEDULER_Task * task;
 
   /**
    * Secondary task to run the operation.
    */
-  GNUNET_SCHEDULER_TaskIdentifier stask;
+  struct GNUNET_SCHEDULER_Task * stask;
 
   /**
    * X-value.
@@ -276,7 +276,7 @@ shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 
   while (NULL != (p = publish_head))
   {
-    if (GNUNET_SCHEDULER_NO_TASK != p->task)
+    if (NULL != p->task)
       GNUNET_SCHEDULER_cancel (p->task);
     if (NULL != p->ctx)
       GNUNET_FS_publish_stop (p->ctx);
@@ -285,9 +285,9 @@ shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   }
   while (NULL != (p = download_head))
   {
-    if (GNUNET_SCHEDULER_NO_TASK != p->task)
+    if (NULL != p->task)
       GNUNET_SCHEDULER_cancel (p->task);
-    if (GNUNET_SCHEDULER_NO_TASK != p->stask)
+    if (NULL != p->stask)
       GNUNET_SCHEDULER_cancel (p->stask);
     if (NULL != p->ctx)
       GNUNET_FS_download_stop (p->ctx, GNUNET_YES);
@@ -320,7 +320,7 @@ publish_stop_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   struct Pattern *p = cls;
 
-  p->task = GNUNET_SCHEDULER_NO_TASK;
+  p->task = NULL;
   GNUNET_FS_publish_stop (p->ctx);
 }
 
@@ -336,7 +336,7 @@ download_stop_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   struct Pattern *p = cls;
 
-  p->task = GNUNET_SCHEDULER_NO_TASK;
+  p->task = NULL;
   GNUNET_FS_download_stop (p->ctx, GNUNET_YES);
 }
 
@@ -352,7 +352,7 @@ search_stop_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   struct Pattern *p = cls;
 
-  p->stask = GNUNET_SCHEDULER_NO_TASK;
+  p->stask = NULL;
   GNUNET_FS_search_stop (p->sctx);
 }
 
@@ -507,7 +507,7 @@ start_publish (void *cls,
   struct Pattern *p = cls;
   struct GNUNET_FS_FileInformation *fi;
 
-  p->task = GNUNET_SCHEDULER_NO_TASK;
+  p->task = NULL;
   if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
     return;
   fi = make_file (p->x, p->y, p);
@@ -532,7 +532,7 @@ start_download (void *cls,
   struct Pattern *p = cls;
   struct GNUNET_FS_Uri *keywords;
 
-  p->task = GNUNET_SCHEDULER_NO_TASK;
+  p->task = NULL;
   if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
     return;
   keywords = make_keywords (p->x);
diff --git a/src/fs/gnunet-fs-profiler.c b/src/fs/gnunet-fs-profiler.c
index 56a3084cc4..ba081f7cf6 100644
--- a/src/fs/gnunet-fs-profiler.c
+++ b/src/fs/gnunet-fs-profiler.c
@@ -50,7 +50,7 @@ static struct GNUNET_TIME_Relative timeout;
 /**
  * Handle to the task run during termination.
  */
-static GNUNET_SCHEDULER_TaskIdentifier terminate_taskid;
+static struct GNUNET_SCHEDULER_Task * terminate_taskid;
 
 
 /**
@@ -115,7 +115,7 @@ static void
 terminate_task (void *cls,
 		const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  terminate_taskid = GNUNET_SCHEDULER_NO_TASK;
+  terminate_taskid = NULL;
   GNUNET_TESTBED_get_statistics (0, NULL,
                                  NULL, NULL,
 				 &process_stats,
diff --git a/src/fs/gnunet-publish.c b/src/fs/gnunet-publish.c
index ceed3109fd..2ec50b14d3 100644
--- a/src/fs/gnunet-publish.c
+++ b/src/fs/gnunet-publish.c
@@ -127,7 +127,7 @@ static int do_disable_creation_time;
 /**
  * Task run on CTRL-C to kill everything nicely.
  */
-static GNUNET_SCHEDULER_TaskIdentifier kill_task;
+static struct GNUNET_SCHEDULER_Task * kill_task;
 
 /**
  * Handle to the directory scanner (for recursive insertions).
@@ -159,7 +159,7 @@ do_stop_task (void *cls,
 {
   struct GNUNET_FS_PublishContext *p;
 
-  kill_task = GNUNET_SCHEDULER_NO_TASK;
+  kill_task = NULL;
   if (NULL != identity)
   {
     GNUNET_IDENTITY_disconnect (identity);
@@ -188,7 +188,7 @@ do_stop_task (void *cls,
 static void
 stop_scanner_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  kill_task = GNUNET_SCHEDULER_NO_TASK;
+  kill_task = NULL;
   if (NULL != ds)
   {
     GNUNET_FS_directory_scan_abort (ds);
@@ -256,10 +256,10 @@ progress_cb (void *cls,
   case GNUNET_FS_STATUS_PUBLISH_ERROR:
     FPRINTF (stderr, _("Error publishing: %s.\n"),
              info->value.publish.specifics.error.message);
-    if (kill_task != GNUNET_SCHEDULER_NO_TASK)
+    if (kill_task != NULL)
     {
       GNUNET_SCHEDULER_cancel (kill_task);
-      kill_task = GNUNET_SCHEDULER_NO_TASK;
+      kill_task = NULL;
     }
     kill_task = GNUNET_SCHEDULER_add_now (&do_stop_task, NULL);
     break;
@@ -284,7 +284,7 @@ progress_cb (void *cls,
     }
     if (NULL == info->value.publish.pctx)
     {
-      if (GNUNET_SCHEDULER_NO_TASK != kill_task)
+      if (NULL != kill_task)
         GNUNET_SCHEDULER_cancel (kill_task);
       kill_task = GNUNET_SCHEDULER_add_now (&do_stop_task, NULL);
     }
@@ -669,10 +669,10 @@ directory_scan_cb (void *cls,
     FPRINTF (stdout,
              "%s",
              _("Internal error scanning directory.\n"));
-    if (kill_task != GNUNET_SCHEDULER_NO_TASK)
+    if (kill_task != NULL)
     {
       GNUNET_SCHEDULER_cancel (kill_task);
-      kill_task = GNUNET_SCHEDULER_NO_TASK;
+      kill_task = NULL;
     }
     kill_task = GNUNET_SCHEDULER_add_now (&stop_scanner_task, NULL);
     break;
diff --git a/src/fs/gnunet-service-fs.c b/src/fs/gnunet-service-fs.c
index 7c8833ce82..4d33626c21 100644
--- a/src/fs/gnunet-service-fs.c
+++ b/src/fs/gnunet-service-fs.c
@@ -167,7 +167,7 @@ static struct GNUNET_CRYPTO_EddsaPrivateKey *pk;
 /**
  * ID of our task that we use to age the cover counters.
  */
-static GNUNET_SCHEDULER_TaskIdentifier cover_age_task;
+static struct GNUNET_SCHEDULER_Task * cover_age_task;
 
 /**
  * Datastore 'GET' load tracking.
@@ -569,10 +569,10 @@ shutdown_task (void *cls,
   block_cfg = NULL;
   GNUNET_STATISTICS_destroy (GSF_stats, GNUNET_NO);
   GSF_stats = NULL;
-  if (GNUNET_SCHEDULER_NO_TASK != cover_age_task)
+  if (NULL != cover_age_task)
   {
     GNUNET_SCHEDULER_cancel (cover_age_task);
-    cover_age_task = GNUNET_SCHEDULER_NO_TASK;
+    cover_age_task = NULL;
   }
   GNUNET_FS_indexing_done ();
   GNUNET_LOAD_value_free (datastore_get_load);
diff --git a/src/fs/gnunet-service-fs_cadet_client.c b/src/fs/gnunet-service-fs_cadet_client.c
index f0905e6c3f..88014f2042 100644
--- a/src/fs/gnunet-service-fs_cadet_client.c
+++ b/src/fs/gnunet-service-fs_cadet_client.c
@@ -140,14 +140,14 @@ struct CadetHandle
    * a few seconds to give the application a chance to give
    * us another query).
    */
-  GNUNET_SCHEDULER_TaskIdentifier timeout_task;
+  struct GNUNET_SCHEDULER_Task * timeout_task;
 
   /**
    * Task to reset cadets that had errors (asynchronously,
    * as we may not be able to do it immediately during a
    * callback from the cadet API).
    */
-  GNUNET_SCHEDULER_TaskIdentifier reset_task;
+  struct GNUNET_SCHEDULER_Task * reset_task;
 
 };
 
@@ -258,7 +258,7 @@ cadet_timeout (void *cls,
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
 	      "Timeout on cadet channel to %s\n",
 	      GNUNET_i2s (&mh->target));
-  mh->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+  mh->timeout_task = NULL;
   tun = mh->channel;
   mh->channel = NULL;
   if(NULL != tun)
@@ -278,7 +278,7 @@ reset_cadet_task (void *cls,
 {
   struct CadetHandle *mh = cls;
 
-  mh->reset_task = GNUNET_SCHEDULER_NO_TASK;
+  mh->reset_task = NULL;
   reset_cadet (mh);
 }
 
@@ -292,7 +292,7 @@ reset_cadet_task (void *cls,
 static void
 reset_cadet_async (struct CadetHandle *mh)
 {
-  if (GNUNET_SCHEDULER_NO_TASK != mh->reset_task)
+  if (NULL != mh->reset_task)
     GNUNET_SCHEDULER_cancel (mh->reset_task);
   mh->reset_task = GNUNET_SCHEDULER_add_now (&reset_cadet_task,
 					     mh);
@@ -527,10 +527,10 @@ get_cadet (const struct GNUNET_PeerIdentity *target)
 					  target);
   if (NULL != mh)
   {
-    if (GNUNET_SCHEDULER_NO_TASK != mh->timeout_task)
+    if (NULL != mh->timeout_task)
     {
       GNUNET_SCHEDULER_cancel (mh->timeout_task);
-      mh->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+      mh->timeout_task = NULL;
     }
     return mh;
   }
@@ -698,9 +698,9 @@ cleaner_cb (void *cls,
 					 mh);
   if (NULL != mh->wh)
     GNUNET_CADET_notify_transmit_ready_cancel (mh->wh);
-  if (GNUNET_SCHEDULER_NO_TASK != mh->timeout_task)
+  if (NULL != mh->timeout_task)
     GNUNET_SCHEDULER_cancel (mh->timeout_task);
-  if (GNUNET_SCHEDULER_NO_TASK != mh->reset_task)
+  if (NULL != mh->reset_task)
     GNUNET_SCHEDULER_cancel (mh->reset_task);
   GNUNET_assert (0 ==
                  GNUNET_CONTAINER_multihashmap_size (mh->waiting_map));
diff --git a/src/fs/gnunet-service-fs_cadet_server.c b/src/fs/gnunet-service-fs_cadet_server.c
index 6ce18afb55..74251e4b79 100644
--- a/src/fs/gnunet-service-fs_cadet_server.c
+++ b/src/fs/gnunet-service-fs_cadet_server.c
@@ -108,12 +108,12 @@ struct CadetClient
   /**
    * Task that is scheduled to asynchronously terminate the connection.
    */
-  GNUNET_SCHEDULER_TaskIdentifier terminate_task;
+  struct GNUNET_SCHEDULER_Task * terminate_task;
 
   /**
    * Task that is scheduled to terminate idle connections.
    */
-  GNUNET_SCHEDULER_TaskIdentifier timeout_task;
+  struct GNUNET_SCHEDULER_Task * timeout_task;
 
   /**
    * Size of the last write that was initiated.
@@ -163,7 +163,7 @@ timeout_cadet_task (void *cls,
   struct CadetClient *sc = cls;
   struct GNUNET_CADET_Channel *tun;
 
-  sc->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+  sc->timeout_task = NULL;
   tun = sc->channel;
   sc->channel = NULL;
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
@@ -181,7 +181,7 @@ timeout_cadet_task (void *cls,
 static void
 refresh_timeout_task (struct CadetClient *sc)
 {
-  if (GNUNET_SCHEDULER_NO_TASK != sc->timeout_task)
+  if (NULL != sc->timeout_task)
     GNUNET_SCHEDULER_cancel (sc->timeout_task);
   sc->timeout_task = GNUNET_SCHEDULER_add_delayed (IDLE_TIMEOUT,
 						   &timeout_cadet_task,
@@ -530,9 +530,9 @@ cleaner_cb (void *cls,
   GNUNET_STATISTICS_update (GSF_stats,
 			    gettext_noop ("# cadet connections active"), -1,
 			    GNUNET_NO);
-  if (GNUNET_SCHEDULER_NO_TASK != sc->terminate_task)
+  if (NULL != sc->terminate_task)
     GNUNET_SCHEDULER_cancel (sc->terminate_task);
-  if (GNUNET_SCHEDULER_NO_TASK != sc->timeout_task)
+  if (NULL != sc->timeout_task)
     GNUNET_SCHEDULER_cancel (sc->timeout_task);
   if (NULL != sc->wh)
     GNUNET_CADET_notify_transmit_ready_cancel (sc->wh);
diff --git a/src/fs/gnunet-service-fs_cp.c b/src/fs/gnunet-service-fs_cp.c
index 030d8b6432..8c956c2749 100644
--- a/src/fs/gnunet-service-fs_cp.c
+++ b/src/fs/gnunet-service-fs_cp.c
@@ -86,7 +86,7 @@ struct GSF_PeerTransmitHandle
   /**
    * Task called on timeout, or 0 for none.
    */
-  GNUNET_SCHEDULER_TaskIdentifier timeout_task;
+  struct GNUNET_SCHEDULER_Task * timeout_task;
 
   /**
    * Function to call to get the actual message.
@@ -155,7 +155,7 @@ struct GSF_DelayedHandle
   /**
    * Task for the delay.
    */
-  GNUNET_SCHEDULER_TaskIdentifier delay_task;
+  struct GNUNET_SCHEDULER_Task * delay_task;
 
   /**
    * Size of the message.
@@ -184,7 +184,7 @@ struct PeerRequest
   /**
    * Task for asynchronous stopping of this request.
    */
-  GNUNET_SCHEDULER_TaskIdentifier kill_task;
+  struct GNUNET_SCHEDULER_Task * kill_task;
 
 };
 
@@ -209,7 +209,7 @@ struct GSF_ConnectedPeer
   /**
    * Task scheduled to revive migration to this peer.
    */
-  GNUNET_SCHEDULER_TaskIdentifier mig_revive_task;
+  struct GNUNET_SCHEDULER_Task * mig_revive_task;
 
   /**
    * Messages (replies, queries, content migration) we would like to
@@ -248,7 +248,7 @@ struct GSF_ConnectedPeer
   /**
    * Task scheduled if we need to retry bandwidth reservation later.
    */
-  GNUNET_SCHEDULER_TaskIdentifier rc_delay_task;
+  struct GNUNET_SCHEDULER_Task * rc_delay_task;
 
   /**
    * Active requests from this neighbour, map of query to 'struct PeerRequest'.
@@ -472,10 +472,10 @@ peer_transmit_ready_cb (void *cls, size_t size, void *buf)
     schedule_transmission (pth);
     return 0;
   }
-  if (GNUNET_SCHEDULER_NO_TASK != pth->timeout_task)
+  if (NULL != pth->timeout_task)
   {
     GNUNET_SCHEDULER_cancel (pth->timeout_task);
-    pth->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+    pth->timeout_task = NULL;
   }
   GNUNET_CONTAINER_DLL_remove (cp->pth_head, cp->pth_tail, pth);
   if (GNUNET_YES == pth->is_query)
@@ -516,7 +516,7 @@ retry_reservation (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   struct GNUNET_PeerIdentity target;
 
   GNUNET_PEER_resolve (cp->ppd.pid, &target);
-  cp->rc_delay_task = GNUNET_SCHEDULER_NO_TASK;
+  cp->rc_delay_task = NULL;
   cp->rc =
     GNUNET_ATS_reserve_bandwidth (GSF_ats, &target, DBLOCK_SIZE,
 				  &ats_reserve_callback, cp);
@@ -652,7 +652,7 @@ revive_migration (void *cls,
   struct GSF_ConnectedPeer *cp = cls;
   struct GNUNET_TIME_Relative bt;
 
-  cp->mig_revive_task = GNUNET_SCHEDULER_NO_TASK;
+  cp->mig_revive_task = NULL;
   bt = GNUNET_TIME_absolute_get_remaining (cp->ppd.migration_blocked_until);
   if (0 != bt.rel_value_us)
   {
@@ -715,7 +715,7 @@ GSF_handle_p2p_migration_stop_ (void *cls,
               GNUNET_i2s (other),
 	      GNUNET_STRINGS_relative_time_to_string (bt, GNUNET_YES));
   cp->ppd.migration_blocked_until = GNUNET_TIME_relative_to_absolute (bt);
-  if (GNUNET_SCHEDULER_NO_TASK == cp->mig_revive_task)
+  if (NULL == cp->mig_revive_task)
   {
     GSF_push_stop_ (cp);
     cp->mig_revive_task =
@@ -773,10 +773,10 @@ free_pending_request (struct PeerRequest *peerreq,
 {
   struct GSF_ConnectedPeer *cp = peerreq->cp;
 
-  if (GNUNET_SCHEDULER_NO_TASK != peerreq->kill_task)
+  if (NULL != peerreq->kill_task)
   {
     GNUNET_SCHEDULER_cancel (peerreq->kill_task);
-    peerreq->kill_task = GNUNET_SCHEDULER_NO_TASK;
+    peerreq->kill_task = NULL;
   }
   GNUNET_STATISTICS_update (GSF_stats, gettext_noop ("# P2P searches active"),
                             -1, GNUNET_NO);
@@ -825,7 +825,7 @@ peer_request_destroy (void *cls,
   struct GSF_PendingRequest *pr = peerreq->pr;
   struct GSF_PendingRequestData *prd;
 
-  peerreq->kill_task = GNUNET_SCHEDULER_NO_TASK;
+  peerreq->kill_task = NULL;
   prd = GSF_pending_request_get_data_ (pr);
   cancel_pending_request (NULL, &prd->query, peerreq);
 }
@@ -987,7 +987,7 @@ handle_p2p_reply (void *cls,
   }
   if (GNUNET_BLOCK_EVALUATION_OK_LAST != eval)
     return;
-  if (GNUNET_SCHEDULER_NO_TASK == peerreq->kill_task)
+  if (NULL == peerreq->kill_task)
   {
     GNUNET_STATISTICS_update (GSF_stats,
                               gettext_noop
@@ -1356,7 +1356,7 @@ peer_transmit_timeout (void *cls,
 
   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
               "Timeout trying to transmit to other peer\n");
-  pth->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+  pth->timeout_task = NULL;
   cp = pth->cp;
   GNUNET_CONTAINER_DLL_remove (cp->pth_head, cp->pth_tail, pth);
   if (GNUNET_YES == pth->is_query)
@@ -1440,10 +1440,10 @@ GSF_peer_transmit_cancel_ (struct GSF_PeerTransmitHandle *pth)
 {
   struct GSF_ConnectedPeer *cp;
 
-  if (GNUNET_SCHEDULER_NO_TASK != pth->timeout_task)
+  if (NULL != pth->timeout_task)
   {
     GNUNET_SCHEDULER_cancel (pth->timeout_task);
-    pth->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+    pth->timeout_task = NULL;
   }
   cp = pth->cp;
   GNUNET_CONTAINER_DLL_remove (cp->pth_head, cp->pth_tail, pth);
@@ -1586,10 +1586,10 @@ GSF_peer_disconnect_handler_ (void *cls,
     GNUNET_ATS_reserve_bandwidth_cancel (cp->rc);
     cp->rc = NULL;
   }
-  if (GNUNET_SCHEDULER_NO_TASK != cp->rc_delay_task)
+  if (NULL != cp->rc_delay_task)
   {
     GNUNET_SCHEDULER_cancel (cp->rc_delay_task);
-    cp->rc_delay_task = GNUNET_SCHEDULER_NO_TASK;
+    cp->rc_delay_task = NULL;
   }
   GNUNET_CONTAINER_multihashmap_iterate (cp->request_map,
                                          &cancel_pending_request, cp);
@@ -1608,10 +1608,10 @@ GSF_peer_disconnect_handler_ (void *cls,
   GNUNET_assert (0 == cp->cth_in_progress);
   while (NULL != (pth = cp->pth_head))
   {
-    if (pth->timeout_task != GNUNET_SCHEDULER_NO_TASK)
+    if (pth->timeout_task != NULL)
     {
       GNUNET_SCHEDULER_cancel (pth->timeout_task);
-      pth->timeout_task = GNUNET_SCHEDULER_NO_TASK;
+      pth->timeout_task = NULL;
     }
     GNUNET_CONTAINER_DLL_remove (cp->pth_head, cp->pth_tail, pth);
     pth->gmc (pth->gmc_cls, 0, NULL);
@@ -1625,10 +1625,10 @@ GSF_peer_disconnect_handler_ (void *cls,
     GNUNET_free (dh);
   }
   GNUNET_PEER_change_rc (cp->ppd.pid, -1);
-  if (GNUNET_SCHEDULER_NO_TASK != cp->mig_revive_task)
+  if (NULL != cp->mig_revive_task)
   {
     GNUNET_SCHEDULER_cancel (cp->mig_revive_task);
-    cp->mig_revive_task = GNUNET_SCHEDULER_NO_TASK;
+    cp->mig_revive_task = NULL;
   }
   GNUNET_free (cp);
 }
diff --git a/src/fs/gnunet-service-fs_lc.c b/src/fs/gnunet-service-fs_lc.c
index 6d3b761bed..0bb5e3f389 100644
--- a/src/fs/gnunet-service-fs_lc.c
+++ b/src/fs/gnunet-service-fs_lc.c
@@ -59,7 +59,7 @@ struct ClientRequest
   /**
    * Task scheduled to destroy the request.
    */
-  GNUNET_SCHEDULER_TaskIdentifier kill_task;
+  struct GNUNET_SCHEDULER_Task * kill_task;
 
 };
 
@@ -193,7 +193,7 @@ client_request_destroy (void *cls,
   struct ClientRequest *cr = cls;
   struct GSF_LocalClient *lc;
 
-  cr->kill_task = GNUNET_SCHEDULER_NO_TASK;
+  cr->kill_task = NULL;
   lc = cr->lc;
   GNUNET_CONTAINER_DLL_remove (lc->cr_head, lc->cr_tail, cr);
   GSF_pending_request_cancel_ (cr->pr, GNUNET_YES);
@@ -242,7 +242,7 @@ client_response_handler (void *cls,
   if (NULL == data)
   {
     /* local-only request, with no result, clean up. */
-    if (GNUNET_SCHEDULER_NO_TASK == cr->kill_task)
+    if (NULL == cr->kill_task)
       cr->kill_task = GNUNET_SCHEDULER_add_now (&client_request_destroy,
                                                 cr);
     return;
@@ -285,7 +285,7 @@ client_response_handler (void *cls,
 		(int) eval);
     return;
   }
-  if (GNUNET_SCHEDULER_NO_TASK == cr->kill_task)
+  if (NULL == cr->kill_task)
     cr->kill_task = GNUNET_SCHEDULER_add_now (&client_request_destroy, cr);
 }
 
@@ -497,7 +497,7 @@ GSF_client_disconnect_handler_ (void *cls,
     return;
   while (NULL != (cr = pos->cr_head))
   {
-    if (GNUNET_SCHEDULER_NO_TASK != cr->kill_task)
+    if (NULL != cr->kill_task)
       GNUNET_SCHEDULER_cancel (cr->kill_task);
     client_request_destroy (cr, NULL);
   }
diff --git a/src/fs/gnunet-service-fs_pe.c b/src/fs/gnunet-service-fs_pe.c
index 07b6b4d652..6b793a1e09 100644
--- a/src/fs/gnunet-service-fs_pe.c
+++ b/src/fs/gnunet-service-fs_pe.c
@@ -196,7 +196,7 @@ struct PeerPlan
   /**
    * Current task for executing the plan.
    */
-  GNUNET_SCHEDULER_TaskIdentifier task;
+  struct GNUNET_SCHEDULER_Task * task;
 };
 
 
@@ -337,7 +337,7 @@ plan (struct PeerPlan *pp, struct GSF_RequestPlan *rp)
                  GNUNET_CONTAINER_multihashmap_contains_value (pp->plan_map,
                                                                get_rp_key (rp),
                                                                rp));
-  if (GNUNET_SCHEDULER_NO_TASK != pp->task)
+  if (NULL != pp->task)
     GNUNET_SCHEDULER_cancel (pp->task);
   pp->task = GNUNET_SCHEDULER_add_now (&schedule_peer_transmission, pp);
 #undef N
@@ -391,7 +391,7 @@ transmit_message_callback (void *cls, size_t buf_size, void *buf)
   if (NULL == buf)
   {
     /* failed, try again... */
-    if (GNUNET_SCHEDULER_NO_TASK != pp->task)
+    if (NULL != pp->task)
       GNUNET_SCHEDULER_cancel (pp->task);
 
     pp->task = GNUNET_SCHEDULER_add_now (&schedule_peer_transmission, pp);
@@ -404,7 +404,7 @@ transmit_message_callback (void *cls, size_t buf_size, void *buf)
   rp = GNUNET_CONTAINER_heap_peek (pp->priority_heap);
   if (NULL == rp)
   {
-    if (GNUNET_SCHEDULER_NO_TASK != pp->task)
+    if (NULL != pp->task)
       GNUNET_SCHEDULER_cancel (pp->task);
     pp->task = GNUNET_SCHEDULER_add_now (&schedule_peer_transmission, pp);
     return 0;
@@ -412,7 +412,7 @@ transmit_message_callback (void *cls, size_t buf_size, void *buf)
   msize = GSF_pending_request_get_message_ (get_latest (rp), buf_size, buf);
   if (msize > buf_size)
   {
-    if (GNUNET_SCHEDULER_NO_TASK != pp->task)
+    if (NULL != pp->task)
       GNUNET_SCHEDULER_cancel (pp->task);
     /* buffer to small (message changed), try again */
     pp->task = GNUNET_SCHEDULER_add_now (&schedule_peer_transmission, pp);
@@ -451,7 +451,7 @@ schedule_peer_transmission (void *cls,
   size_t msize;
   struct GNUNET_TIME_Relative delay;
 
-  pp->task = GNUNET_SCHEDULER_NO_TASK;
+  pp->task = NULL;
   if (NULL != pp->pth)
   {
     GSF_peer_transmit_cancel_ (pp->pth);
@@ -661,10 +661,10 @@ GSF_plan_notify_peer_disconnect_ (const struct GSF_ConnectedPeer *cp)
     GSF_peer_transmit_cancel_ (pp->pth);
     pp->pth = NULL;
   }
-  if (GNUNET_SCHEDULER_NO_TASK != pp->task)
+  if (NULL != pp->task)
   {
     GNUNET_SCHEDULER_cancel (pp->task);
-    pp->task = GNUNET_SCHEDULER_NO_TASK;
+    pp->task = NULL;
   }
   while (NULL != (rp = GNUNET_CONTAINER_heap_remove_root (pp->priority_heap)))
   {
diff --git a/src/fs/gnunet-service-fs_pr.c b/src/fs/gnunet-service-fs_pr.c
index f809efd6ce..5dc03393a3 100644
--- a/src/fs/gnunet-service-fs_pr.c
+++ b/src/fs/gnunet-service-fs_pr.c
@@ -157,7 +157,7 @@ struct GSF_PendingRequest
   /**
    * Task that warns us if the local datastore lookup takes too long.
    */
-  GNUNET_SCHEDULER_TaskIdentifier warn_task;
+  struct GNUNET_SCHEDULER_Task * warn_task;
 
   /**
    * Current offset for querying our local datastore for results.
@@ -632,10 +632,10 @@ clean_request (void *cls, const struct GNUNET_HashCode *key, void *value)
     GNUNET_DHT_get_stop (pr->gh);
     pr->gh = NULL;
   }
-  if (GNUNET_SCHEDULER_NO_TASK != pr->warn_task)
+  if (NULL != pr->warn_task)
   {
     GNUNET_SCHEDULER_cancel (pr->warn_task);
-    pr->warn_task = GNUNET_SCHEDULER_NO_TASK;
+    pr->warn_task = NULL;
   }
   GNUNET_assert (GNUNET_OK ==
                  GNUNET_CONTAINER_multihashmap_remove (pr_map,
@@ -690,10 +690,10 @@ GSF_pending_request_cancel_ (struct GSF_PendingRequest *pr, int full_cleanup)
       GNUNET_DHT_get_stop (pr->gh);
       pr->gh = NULL;
     }
-    if (GNUNET_SCHEDULER_NO_TASK != pr->warn_task)
+    if (NULL != pr->warn_task)
     {
       GNUNET_SCHEDULER_cancel (pr->warn_task);
-      pr->warn_task = GNUNET_SCHEDULER_NO_TASK;
+      pr->warn_task = NULL;
     }
     return;
   }
@@ -1307,7 +1307,7 @@ process_local_reply (void *cls, const struct GNUNET_HashCode * key, size_t size,
   unsigned int old_rf;
 
   GNUNET_SCHEDULER_cancel (pr->warn_task);
-  pr->warn_task = GNUNET_SCHEDULER_NO_TASK;
+  pr->warn_task = NULL;
   if (NULL != pr->qe)
   {
     pr->qe = NULL;
@@ -1514,10 +1514,10 @@ process_local_reply (void *cls, const struct GNUNET_HashCode * key, size_t size,
 check_error_and_continue:
   if (NULL != pr->qe)
     return;
-  if (GNUNET_SCHEDULER_NO_TASK != pr->warn_task)
+  if (NULL != pr->warn_task)
   {
     GNUNET_SCHEDULER_cancel (pr->warn_task);
-    pr->warn_task = GNUNET_SCHEDULER_NO_TASK;
+    pr->warn_task = NULL;
   }
   if (NULL == (cont = pr->llc_cont))
     return;                     /* no continuation */
@@ -1620,7 +1620,7 @@ GSF_local_lookup_ (struct GSF_PendingRequest *pr,
                             ("# Datastore lookups concluded (error queueing)"),
                             1, GNUNET_NO);
   GNUNET_SCHEDULER_cancel (pr->warn_task);
-  pr->warn_task = GNUNET_SCHEDULER_NO_TASK;
+  pr->warn_task = NULL;
   pr->llc_cont = NULL;
   if (NULL != cont)
     cont (cont_cls, pr, pr->local_result);
diff --git a/src/fs/gnunet-service-fs_push.c b/src/fs/gnunet-service-fs_push.c
index f099f7fdce..88c92828f5 100644
--- a/src/fs/gnunet-service-fs_push.c
+++ b/src/fs/gnunet-service-fs_push.c
@@ -163,7 +163,7 @@ static struct GNUNET_DATASTORE_QueueEntry *mig_qe;
 /**
  * ID of task that collects blocks for migration.
  */
-static GNUNET_SCHEDULER_TaskIdentifier mig_task;
+static struct GNUNET_SCHEDULER_Task * mig_task;
 
 /**
  * What is the maximum frequency at which we are allowed to
@@ -452,7 +452,7 @@ consider_gathering ()
     return;
   if (NULL != mig_qe)
     return;
-  if (GNUNET_SCHEDULER_NO_TASK != mig_task)
+  if (NULL != mig_task)
     return;
   if (mig_size >= MAX_MIGRATION_QUEUE)
     return;
@@ -575,7 +575,7 @@ static void
 gather_migration_blocks (void *cls,
                          const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  mig_task = GNUNET_SCHEDULER_NO_TASK;
+  mig_task = NULL;
   if (mig_size >= MAX_MIGRATION_QUEUE)
     return;
   if (NULL == GSF_dsh)
@@ -682,10 +682,10 @@ GSF_push_init_ ()
 void
 GSF_push_done_ ()
 {
-  if (GNUNET_SCHEDULER_NO_TASK != mig_task)
+  if (NULL != mig_task)
   {
     GNUNET_SCHEDULER_cancel (mig_task);
-    mig_task = GNUNET_SCHEDULER_NO_TASK;
+    mig_task = NULL;
   }
   if (NULL != mig_qe)
   {
diff --git a/src/fs/gnunet-service-fs_put.c b/src/fs/gnunet-service-fs_put.c
index 8e9d70f72c..9eef491daa 100644
--- a/src/fs/gnunet-service-fs_put.c
+++ b/src/fs/gnunet-service-fs_put.c
@@ -63,7 +63,7 @@ struct PutOperator
   /**
    * ID of task that collects blocks for DHT PUTs.
    */
-  GNUNET_SCHEDULER_TaskIdentifier dht_task;
+  struct GNUNET_SCHEDULER_Task * dht_task;
 
   /**
    * How many entires with zero anonymity of our type do we currently
@@ -158,7 +158,7 @@ delay_dht_put_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   struct PutOperator *po = cls;
 
-  po->dht_task = GNUNET_SCHEDULER_NO_TASK;
+  po->dht_task = NULL;
   schedule_next_put (po);
 }
 
@@ -219,7 +219,7 @@ gather_dht_put_blocks (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   struct PutOperator *po = cls;
 
-  po->dht_task = GNUNET_SCHEDULER_NO_TASK;
+  po->dht_task = NULL;
   if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
     return;
   po->dht_qe =
@@ -263,10 +263,10 @@ GSF_put_done_ ()
   i = 0;
   while ((po = &operators[i])->dht_put_type != GNUNET_BLOCK_TYPE_ANY)
   {
-    if (GNUNET_SCHEDULER_NO_TASK != po->dht_task)
+    if (NULL != po->dht_task)
     {
       GNUNET_SCHEDULER_cancel (po->dht_task);
-      po->dht_task = GNUNET_SCHEDULER_NO_TASK;
+      po->dht_task = NULL;
     }
     if (NULL != po->dht_put)
     {
diff --git a/src/fs/test_fs_download.c b/src/fs/test_fs_download.c
index 8dee249126..94e7e0733d 100644
--- a/src/fs/test_fs_download.c
+++ b/src/fs/test_fs_download.c
@@ -57,7 +57,7 @@ static struct GNUNET_FS_DownloadContext *download;
 
 static struct GNUNET_FS_PublishContext *publish;
 
-static GNUNET_SCHEDULER_TaskIdentifier timeout_kill;
+static struct GNUNET_SCHEDULER_Task * timeout_kill;
 
 static char *fn;
 
@@ -80,7 +80,7 @@ timeout_kill_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
     publish = NULL;
   }
   GNUNET_log (GNUNET_ERROR_TYPE_ERROR, "Timeout downloading file\n");
-  timeout_kill = GNUNET_SCHEDULER_NO_TASK;
+  timeout_kill = NULL;
   err = 1;
 }
 
@@ -120,7 +120,7 @@ abort_download_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   GNUNET_free (fn);
   fn = NULL;
   GNUNET_SCHEDULER_cancel (timeout_kill);
-  timeout_kill = GNUNET_SCHEDULER_NO_TASK;
+  timeout_kill = NULL;
 }
 
 
diff --git a/src/fs/test_fs_download_persistence.c b/src/fs/test_fs_download_persistence.c
index a9b9980139..7e1f01ae71 100644
--- a/src/fs/test_fs_download_persistence.c
+++ b/src/fs/test_fs_download_persistence.c
@@ -54,7 +54,7 @@ static struct GNUNET_FS_DownloadContext *download;
 
 static struct GNUNET_FS_PublishContext *publish;
 
-static GNUNET_SCHEDULER_TaskIdentifier timeout_kill;
+static struct GNUNET_SCHEDULER_Task * timeout_kill;
 
 static char *fn;
 
@@ -75,7 +75,7 @@ timeout_kill_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
     GNUNET_FS_publish_stop (publish);
     publish = NULL;
   }
-  timeout_kill = GNUNET_SCHEDULER_NO_TASK;
+  timeout_kill = NULL;
   err = 1;
 }
 
@@ -107,7 +107,7 @@ abort_download_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   GNUNET_free (fn);
   fn = NULL;
   GNUNET_SCHEDULER_cancel (timeout_kill);
-  timeout_kill = GNUNET_SCHEDULER_NO_TASK;
+  timeout_kill = NULL;
 }
 
 
diff --git a/src/fs/test_fs_namespace.c b/src/fs/test_fs_namespace.c
index c780081222..461bfdcdd6 100644
--- a/src/fs/test_fs_namespace.c
+++ b/src/fs/test_fs_namespace.c
@@ -41,7 +41,7 @@ static struct GNUNET_FS_SearchContext *sks_search;
 
 static struct GNUNET_FS_SearchContext *ksk_search;
 
-static GNUNET_SCHEDULER_TaskIdentifier kill_task;
+static struct GNUNET_SCHEDULER_Task * kill_task;
 
 static int update_started;
 
@@ -58,7 +58,7 @@ abort_ksk_search_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
     if (sks_search == NULL)
     {
       GNUNET_FS_stop (fs);
-      if (GNUNET_SCHEDULER_NO_TASK != kill_task)
+      if (NULL != kill_task)
         GNUNET_SCHEDULER_cancel (kill_task);
     }
   }
@@ -75,7 +75,7 @@ abort_sks_search_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   if (ksk_search == NULL)
   {
     GNUNET_FS_stop (fs);
-    if (GNUNET_SCHEDULER_NO_TASK != kill_task)
+    if (NULL != kill_task)
       GNUNET_SCHEDULER_cancel (kill_task);
   }
 }
@@ -86,7 +86,7 @@ do_timeout (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   err = 1;
   FPRINTF (stderr, "%s",  "Operation timed out\n");
-  kill_task = GNUNET_SCHEDULER_NO_TASK;
+  kill_task = NULL;
   abort_sks_search_task (NULL, tc);
   abort_ksk_search_task (NULL, tc);
 }
diff --git a/src/fs/test_fs_publish_persistence.c b/src/fs/test_fs_publish_persistence.c
index 8e5e5f53bf..3c8b6e34e9 100644
--- a/src/fs/test_fs_publish_persistence.c
+++ b/src/fs/test_fs_publish_persistence.c
@@ -60,7 +60,7 @@ static char *fn2;
 
 static int err;
 
-static GNUNET_SCHEDULER_TaskIdentifier rtask;
+static struct GNUNET_SCHEDULER_Task * rtask;
 
 
 static void
@@ -76,10 +76,10 @@ abort_publish_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   fn2 = NULL;
   GNUNET_FS_stop (fs);
   fs = NULL;
-  if (GNUNET_SCHEDULER_NO_TASK != rtask)
+  if (NULL != rtask)
   {
     GNUNET_SCHEDULER_cancel (rtask);
-    rtask = GNUNET_SCHEDULER_NO_TASK;
+    rtask = NULL;
   }
 }
 
@@ -91,7 +91,7 @@ progress_cb (void *cls, const struct GNUNET_FS_ProgressInfo *event);
 static void
 restart_fs_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  rtask = GNUNET_SCHEDULER_NO_TASK;
+  rtask = NULL;
   GNUNET_FS_stop (fs);
   fs = GNUNET_FS_start (cfg, "test-fs-publish-persistence",
 			&progress_cb, NULL,
diff --git a/src/fs/test_fs_search.c b/src/fs/test_fs_search.c
index f525fb474a..caf2898b28 100644
--- a/src/fs/test_fs_search.c
+++ b/src/fs/test_fs_search.c
@@ -52,7 +52,7 @@ static struct GNUNET_FS_SearchContext *search;
 
 static struct GNUNET_FS_PublishContext *publish;
 
-static GNUNET_SCHEDULER_TaskIdentifier timeout_task;
+static struct GNUNET_SCHEDULER_Task * timeout_task;
 
 static int err;
 
@@ -65,10 +65,10 @@ abort_publish_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
     GNUNET_FS_publish_stop (publish);
     publish = NULL;
   }
-  if (GNUNET_SCHEDULER_NO_TASK != timeout_task)
+  if (NULL != timeout_task)
   {
     GNUNET_SCHEDULER_cancel (timeout_task);
-    timeout_task = GNUNET_SCHEDULER_NO_TASK;
+    timeout_task = NULL;
   }
 }
 
@@ -78,7 +78,7 @@ abort_error (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   fprintf (stderr,
 	   "Timeout\n");
-  timeout_task = GNUNET_SCHEDULER_NO_TASK;
+  timeout_task = NULL;
   if (NULL != search)
   {
     GNUNET_FS_search_stop (search);
diff --git a/src/fs/test_fs_search_persistence.c b/src/fs/test_fs_search_persistence.c
index 34ea04acad..780f21d994 100644
--- a/src/fs/test_fs_search_persistence.c
+++ b/src/fs/test_fs_search_persistence.c
@@ -54,7 +54,7 @@ static struct GNUNET_FS_PublishContext *publish;
 
 static const struct GNUNET_CONFIGURATION_Handle *cfg;
 
-static GNUNET_SCHEDULER_TaskIdentifier timeout_task;
+static struct GNUNET_SCHEDULER_Task * timeout_task;
 
 static int err;
 
@@ -62,7 +62,7 @@ static int err;
 static void
 abort_error (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  timeout_task = GNUNET_SCHEDULER_NO_TASK;
+  timeout_task = NULL;
   fprintf (stderr,
 	   "Timeout\n");
   if (NULL != search)
@@ -86,10 +86,10 @@ abort_publish_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
     GNUNET_FS_publish_stop (publish);
     publish = NULL;
   }
-  if (GNUNET_SCHEDULER_NO_TASK != timeout_task)
+  if (NULL != timeout_task)
   {
     GNUNET_SCHEDULER_cancel (timeout_task);
-    timeout_task = GNUNET_SCHEDULER_NO_TASK;
+    timeout_task = NULL;
   }
 }
 
diff --git a/src/fs/test_fs_search_probes.c b/src/fs/test_fs_search_probes.c
index beae34763c..c7abd073f1 100644
--- a/src/fs/test_fs_search_probes.c
+++ b/src/fs/test_fs_search_probes.c
@@ -53,7 +53,7 @@ static struct GNUNET_FS_SearchContext *search;
 
 static struct GNUNET_FS_PublishContext *publish;
 
-static GNUNET_SCHEDULER_TaskIdentifier timeout_task;
+static struct GNUNET_SCHEDULER_Task * timeout_task;
 
 static int err;
 
@@ -61,7 +61,7 @@ static int err;
 static void
 abort_error (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  timeout_task = GNUNET_SCHEDULER_NO_TASK;
+  timeout_task = NULL;
   fprintf (stderr,
 	   "Timeout\n");
   if (NULL != search)
@@ -86,10 +86,10 @@ abort_publish_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
     GNUNET_FS_publish_stop (publish);
     publish = NULL;
   }
-  if (GNUNET_SCHEDULER_NO_TASK != timeout_task)
+  if (NULL != timeout_task)
   {
     GNUNET_SCHEDULER_cancel (timeout_task);
-    timeout_task = GNUNET_SCHEDULER_NO_TASK;
+    timeout_task = NULL;
   }
 }
 
diff --git a/src/fs/test_fs_search_with_and.c b/src/fs/test_fs_search_with_and.c
index 80cd03213a..cca0e342e2 100644
--- a/src/fs/test_fs_search_with_and.c
+++ b/src/fs/test_fs_search_with_and.c
@@ -58,7 +58,7 @@ static struct GNUNET_FS_SearchContext *search;
 
 static struct GNUNET_FS_PublishContext *publish;
 
-static GNUNET_SCHEDULER_TaskIdentifier timeout_task;
+static struct GNUNET_SCHEDULER_Task * timeout_task;
 
 static int err;
 
@@ -73,10 +73,10 @@ abort_publish_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
     GNUNET_FS_publish_stop (publish);
     publish = NULL;
   }
-  if (GNUNET_SCHEDULER_NO_TASK != timeout_task)
+  if (NULL != timeout_task)
   {
     GNUNET_SCHEDULER_cancel (timeout_task);
-    timeout_task = GNUNET_SCHEDULER_NO_TASK;
+    timeout_task = NULL;
   }
 }
 
@@ -86,7 +86,7 @@ abort_error (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
   fprintf (stderr,
 	   "Timeout\n");
-  timeout_task = GNUNET_SCHEDULER_NO_TASK;
+  timeout_task = NULL;
   if (NULL != search)
   {
     GNUNET_FS_search_stop (search);