--- libaitsched/src/aitsched.c	2024/02/26 12:58:55	1.36
+++ libaitsched/src/aitsched.c	2024/03/20 12:48:45	1.36.4.1
@@ -3,7 +3,7 @@
 *  by Michael Pounov <misho@openbsd-bg.org>
 *
 * $Author: misho $
-* $Id: aitsched.c,v 1.36 2024/02/26 12:58:55 misho Exp $
+* $Id: aitsched.c,v 1.36.4.1 2024/03/20 12:48:45 misho Exp $
 *
 **************************************************************************
 The ELWIX and AITNET software is distributed under the following
@@ -54,7 +54,9 @@ char sched_Error[STRSIZ];
 
 #pragma GCC visibility pop
 
+volatile pthread_t sched_sigThr;
 
+
 // sched_GetErrno() Get error code of last operation
 int
 sched_GetErrno()
@@ -1074,7 +1076,7 @@ schedPolling(sched_root_task_t * __restrict root, stru
 int
 schedTermCondition(sched_root_task_t * __restrict root, intptr_t * __restrict condValue)
 {
-	if (!root && !condValue)
+	if (!root || !condValue)
 		return -1;
 
 	*root->root_cond = *condValue;
@@ -1189,7 +1191,7 @@ _sched_sigDisp(void *arg)
  *
  * @root = root task
  * @on = Activate or =0 deactivate
- * return: -1 error or 0 ok
+ * return: -1 error, 1 already started, 2 another thread already started or 0 ok
  */
 int
 schedSignalDispatch(sched_root_task_t * __restrict root, int on)
@@ -1208,20 +1210,25 @@ schedSignalDispatch(sched_root_task_t * __restrict roo
 #endif
 
 	if (!on) {
-		if (root->root_sigthr)
+		if (root->root_sigthr) {
+			if (root->root_sigthr == sched_sigThr) {
+#ifdef __linux__
+				sched_sigThr = 0L;
+#else
+				sched_sigThr = NULL;
+#endif
+			}
 			pthread_cancel(root->root_sigthr);
 #ifdef __linux__
-		root->root_sigthr = 0L;
+			root->root_sigthr = 0L;
 #else
-		root->root_sigthr = NULL;
+			root->root_sigthr = NULL;
 #endif
+		}
+
 		return 0;
 	}
 
-	/* if we have already started signal thread, then skip routine */
-	if (root->root_sigthr)
-		return 0;
-
 	/* if we have not using polling, then we must turn on */
 	if (sched_timespecisinf(&root->root_poll))
 		schedPolling(root, &ts, NULL);
@@ -1234,6 +1241,12 @@ schedSignalDispatch(sched_root_task_t * __restrict roo
 	pthread_attr_setschedpolicy(&attr, SCHED_OTHER);
 #endif
 
+	/* if we have already started signal thread, then skip routine */
+	if (root->root_sigthr)
+		return 1;
+	if (sched_sigThr)
+		return 2;
+
 	sigfillset(&ss);
 	pthread_sigmask(SIG_BLOCK, &ss, NULL);
 
@@ -1247,7 +1260,8 @@ schedSignalDispatch(sched_root_task_t * __restrict roo
 #endif
 		pthread_sigmask(SIG_SETMASK, &root->root_oldset, NULL);
 		return -1;
-	}
+	} else
+		sched_sigThr = root->root_sigthr;
 
 	return 0;
 }