WEBVTT 00:05.010 --> 00:07.410 So, guys, now let us discuss the point number three. 00:07.410 --> 00:08.880 That is thread termination. 00:08.910 --> 00:14.940 It simply means that when a new thread is created, then in how many ways a new thread can be terminated. 00:15.300 --> 00:19.170 So there are three ways in which a thread can be terminated. 00:19.350 --> 00:23.190 A thread can simply terminate if its thread function returns. 00:23.190 --> 00:27.300 That is, its thread function runs to completion successfully. 00:27.300 --> 00:28.080 Right. 00:28.290 --> 00:33.300 A thread can also be terminated if it invokes an api p thread underscore exit. 00:33.300 --> 00:34.080 Right. 00:34.230 --> 00:41.580 And the third way of terminating a thread is that if some other thread kills or cancels the thread. 00:41.580 --> 00:42.180 Right. 00:42.180 --> 00:45.030 So the third point refers to as thread cancellation. 00:45.030 --> 00:49.710 And we were going to discuss this thread cancellation in pretty much detail in the future section of 00:49.710 --> 00:50.520 this course. 00:50.940 --> 00:54.630 So now through our Hello World example, let us discuss the first two points. 00:54.630 --> 01:00.360 That is when the thread function returns and if the thread invokes an api p thread exit. 01:00.810 --> 01:07.150 So in our Hello world example our child thread actually never terminates because it was executing in 01:07.150 --> 01:09.430 the while loop, which is an infinite loop. 01:09.430 --> 01:10.000 Right. 01:11.840 --> 01:19.220 So if simply change the condition here, let's say I take a variable int a is equal to zero. 01:19.220 --> 01:25.700 And here if I simply check that, execute as long as a is less than ten. 01:26.090 --> 01:27.050 Right. 01:27.260 --> 01:32.810 So now our child thread is not immortal and it will going to end in some time. 01:32.810 --> 01:33.400 Right? 01:33.410 --> 01:38.150 In fact, in 10s our child thread function will going to terminate. 01:38.240 --> 01:43.400 Now why the child thread terminate because its thread function would end right? 01:43.400 --> 01:44.600 It would return. 01:45.170 --> 01:47.870 So this is one way how a thread terminate. 01:47.900 --> 01:54.630 The second way is that that the child thread during its execution invokes an API thread underscore exit. 01:54.650 --> 02:04.310 So here if I simply type out that if a is equal equal five, then I want to terminate my thread. 02:05.090 --> 02:09.590 So what I'm going to do is that simply invoke an API thread. 02:09.590 --> 02:10.460 Exit zero. 02:10.920 --> 02:16.830 So this is one way in which my child thread gets terminated using an API thread. 02:16.830 --> 02:18.110 Underscore exit. 02:18.120 --> 02:18.840 Right. 02:18.930 --> 02:25.320 Now what does that zero represent in the bracket that we will going to discuss in detail in the subsequent 02:25.320 --> 02:26.640 section of this course. 02:26.940 --> 02:32.760 So you can make these little changes in your Hello World program that you have written and try out. 02:33.720 --> 02:36.670 Coming to the third point, that is thread cancellation. 02:36.690 --> 02:42.990 So here thread cancellation simply means that one thread is canceled or terminated by other thread. 02:43.020 --> 02:50.070 So in this example you can say that the thread t one creates a thread t two at the fourth point f right. 02:51.170 --> 02:57.290 Now let us suppose that the thread T2 is doing its work and it is somewhere doing its work at point 02:57.320 --> 02:57.890 B. 02:58.190 --> 03:00.200 Point B is some instruction. 03:00.290 --> 03:03.800 Point B is some instruction in the execution flow of the thread. 03:03.830 --> 03:05.210 T2 right. 03:05.240 --> 03:10.100 Now thread t1 wishes to terminate the thread t2 right. 03:10.100 --> 03:18.020 So thread t1 at any point of time can send the cancel request to the thread t2 right. 03:18.050 --> 03:25.130 When this cancel request is received by the thread t2 it don't matter what thread t2 was busy with, 03:25.160 --> 03:27.770 it will get terminated right. 03:28.280 --> 03:34.550 Now note that it is not necessary that it is only the parent thread which can cancel child thread. 03:34.580 --> 03:37.970 Even child thread can also cancel the parent thread. 03:38.570 --> 03:39.290 Right. 03:39.470 --> 03:42.230 So any thread can cancel any other thread. 03:42.260 --> 03:45.800 In fact, one thread can cancel many other threads. 03:45.800 --> 03:46.430 Right. 03:46.430 --> 03:47.660 So it all depends. 03:47.660 --> 03:51.500 Sending this cancellation request to the thread. 03:51.500 --> 03:55.400 A thread which receives this cancellation request will get cancelled. 03:55.610 --> 04:00.590 So we will discuss in detail regarding thread cancellation in the future section of this course. 04:00.620 --> 04:06.320 For now I have just given an overview that cancellation of the thread is the third way in which a thread 04:06.320 --> 04:08.330 can be cancelled or terminated.