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So let's make some script where we can use vinyl.

2
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Great file called print as age on the first line start shoving been Bash and what we are going to build

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here.

4
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We will create a script for a reading.

5
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Or maybe it would be better to say for printing files which will display also

6
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line numbers.

7
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So basically we are going to build something similar to copy command but we will also line numbers script

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to take only one argument and that will be filed by.

9
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So we can start with argument check if number of arguments is different from one

10
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then we can fit into zero.

11
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Exactly.

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One argument is needed

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around the live sign is 0 which is in our script which is our script name.

14
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And this will be followed by file path.

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And of course exit rate start those run here.

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Now we can assign value of that first argument into a variable called Fireline

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and as we need to count blind numbers we need some counters so craved variable count and assigned number

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1 to it.

19
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Now if actually reading we can write.

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While read line we can use an other different variable name as for example Vohra but the convention

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here is to line

22
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and for each line we will perform some commands between keyboards do and dumb.

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So we will print a line number represented by variable count

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and then we will print on the same line.

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The actual line from file

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and of course we need to increase Kantar here.

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So we see correct lines and line numbers.

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Now we need to provide some data into viable.

29
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So we will direct our file pop into vinyl loops standart input

30
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scrape is down but it would be nice to do some checking if provided argument is an existing file

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so we can firstly create some command about it.

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Check

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if provided command

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is efile.

35
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So if file exists so I am using operand and maybe better would be to ask if that file doesn't exist.

36
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So I I will negate this by prepending exclamation mark.

37
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And then we can print to screen file.

38
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You have specified

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does not exist.

40
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And we can of course exit here with some status.

41
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For example it starts to now we can save descript

42
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ground with permissions

43
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and we can also create some test file which then will be read by our ascript

44
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So some data we'd like one line to something here.

45
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Something else like the five save the file and we can now print that file by using our script

46
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Oh that's nice.

47
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We see all lines but we also see a line numbering.

48
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Great.

49
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Now let's open some bigger file for example Basford file

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grade.

51
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It is working.

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I see in my case 41 lines.

53
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Pretty amazing.

54
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Do you remember on Tillery lecture where I told you that we have another option how to read files.

55
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So let's try but firstly I will copy our script and rename it to print to good as a

56
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we can open it

57
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and just before the start of a viable up we will provide data.

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Do it using pipe Soave right.

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Got file name

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type

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and of course delete file name variable next to Dom keyboard

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we can save it

63
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and RAM to see if it is working.

64
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And I am using passport file again.

65
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And it is working great.

66
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But now let's do some interesting experiment with internal field separator.

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I will firstly clear the screen

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then open print s age and they remove double quotation marks next to file name variable

69
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save descript

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Now Kobe.

71
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Our test file and rename it to hello body dot text with the space between the hello and body.

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Now if you want to print Hello body file

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we are receiving error message Eevee printed with installed or s h

74
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we can see content of that file so only one difference here is removed quotation marks for file name

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variable.

76
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But of-I it is behaving this way.

77
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Firstly check the value of internal fields separator

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Visi that fields are separated by space DUP and New Line as if you didn't use for a file and pop quotation

79
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marks.

80
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It separated our file a whole body because there is a space in the name of dead file.

81
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But what would happen if we change into now field separator to only new lines then our file our whole

82
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body wouldn't be separated and rendered under script.

83
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We should see file content.

84
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So let's experiment open into dot S H

85
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and set into another field separator to be separated only on a new line

86
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you noticed that at the beginning.

87
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We have dollar sign.

88
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If we didn't use it it would in our case separate.

89
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Not on a new line but on a character end and also on backslash character.

90
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So basically it means when we are using Dorsai in backslash is not a normal backslash but it is now.

91
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Escape character which together with any character means new line.

92
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So now save the script and add on discrete different fields separated

93
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and it is working.

94
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We have changed internat field separator to a new line.

95
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So now we can see content of a whole body file because in a whole body file name is no new line character

96
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which would separate the file name.

97
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So advice here is to always use double quotation marks when reading files or even checking if they exist.