1 00:00:01,680 --> 00:00:05,730 In this lecture we are starting from some not empathy for the other. 2 00:00:05,770 --> 00:00:08,430 For example I have three files. 3 00:00:08,440 --> 00:00:13,810 You know we see that the standard output stream is printed to them now. 4 00:00:13,840 --> 00:00:14,900 So let's change it. 5 00:00:14,920 --> 00:00:16,930 And I did check it out. 6 00:00:17,300 --> 00:00:19,770 Text. 7 00:00:20,010 --> 00:00:28,540 And if you check is inside output text you see that it contains output of a command. 8 00:00:29,520 --> 00:00:32,690 Now we can read the text on that stream to some file 9 00:00:39,210 --> 00:00:44,310 and we see that standard output stream is still default reprinted to do now. 10 00:00:44,490 --> 00:00:52,310 And when we check Eriphyle we see that it this empathy as there was no issue running at us. 11 00:00:52,460 --> 00:00:55,870 CONAN Now let's make some errors. 12 00:00:55,900 --> 00:01:02,290 I'm using percentage symbol for a month and I know that this action should throw an error because there 13 00:01:02,290 --> 00:01:03,860 is no such a file. 14 00:01:04,060 --> 00:01:12,020 And I really really read standard Aeros stream to error text file reseeded standard. 15 00:01:12,060 --> 00:01:16,040 There was nothing printed as we don't see anything printed to the terminal. 16 00:01:16,050 --> 00:01:22,250 Let's check at our file and we see the error message which was provided by a SQL month to standard or 17 00:01:22,350 --> 00:01:22,970 Stream. 18 00:01:23,020 --> 00:01:27,960 And then it had directed to this file. 19 00:01:27,960 --> 00:01:35,760 Now we want to correct both the standard output and standard error streams to one file and we can call 20 00:01:35,760 --> 00:01:37,920 it bold dot text. 21 00:01:42,940 --> 00:01:49,190 And we see the error message from standard error stream printed in that file. 22 00:01:50,830 --> 00:01:53,980 We can now redirect both streams to different files. 23 00:01:53,980 --> 00:02:03,160 So standard output to output dot text and standard error stream to error that text file 24 00:02:07,620 --> 00:02:08,650 and see 25 00:02:11,590 --> 00:02:18,920 that only after that text file has some output. 26 00:02:19,020 --> 00:02:20,140 Great. 27 00:02:20,300 --> 00:02:27,660 Now will they extend that output to some file and add or stream we can that I detect to standard output 28 00:02:31,590 --> 00:02:35,910 so to greater then the symbol unperson one 29 00:02:40,350 --> 00:02:43,860 and if we check output growth textfile 30 00:02:47,270 --> 00:02:53,240 we see error message from standard error stream which was already addicted to standard output stream 31 00:02:53,360 --> 00:02:59,900 and this output stream most had detected to file out with good backs. 32 00:03:00,260 --> 00:03:04,370 Now clear the screen and we can try some piping. 33 00:03:05,350 --> 00:03:12,510 Firstly I will check what files are in my directory and I can using redirection display a number of 34 00:03:12,510 --> 00:03:18,340 lines of some file if you want to do that using piping. 35 00:03:18,360 --> 00:03:26,900 We need to send output of cat command to WC come on through using pipe within those comments. 36 00:03:27,200 --> 00:03:28,950 Now let's make it more difficult. 37 00:03:29,000 --> 00:03:33,890 Despite only first five lines of output provided by catechumen 38 00:03:38,200 --> 00:03:44,340 and we can continue on display only last two lines of output provided by head command. 39 00:03:44,770 --> 00:03:48,180 So we see fault and FirstLine. 40 00:03:48,240 --> 00:03:51,430 Now let's count how many lines we have. 41 00:03:51,760 --> 00:03:59,190 And obviously if we have only two lines now and don't forget that we can detect final output of those 42 00:03:59,190 --> 00:04:01,410 piping commands into a file 43 00:04:06,500 --> 00:04:12,540 and recheck that file we see the same output. 44 00:04:13,160 --> 00:04:13,790 Yes. 45 00:04:13,820 --> 00:04:17,800 Number two as was previously displayed to the screen. 46 00:04:17,930 --> 00:04:18,360 Great.