Penguin
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Annotated edit history of AWKNotes version 4 showing authors affecting page license. View with all changes included.
Rev Author # Line
1 BenStaz 1 !The Field Separator
2
3 It doesn't just have to white space between fields. In can be anything as long as you set the appropriate field separator.
4 Eg:
5 *echo "123:456:789" | awk -F ':' '{print $1,$2,$3,}'
6
7 The '':'' after the ''-F'' tells us that '':'' is the input field separator. Change this as appropriate.
8
9 !Multiple Field Separators.
10
11 What if there are multiple characters you wish to use as field separators?
12 After the ''-F'' just list all of the characters in square brackets.
13 For example:
14
15 *echo "123:456=789" | awk -F '~[:=]' '{print $1,$2,$3}'
2 BenStaz 16
17 !Using Bash Variables inside awk.
18
19 To use the value of a bash variable. You have to use the ''-v'' switch to import it.
20 The syntax is:
21
22 *awk -v awkvar=$bashvar {print awkvar}
23
24 Now you can use awkvar in your awk statements which will have the value of bashvar.
25 Remember you *CANNOT* change the value of a bash variable using [AWK].
4 AlastairPorter 26
27 ! Floating point output
28 you can use printf modifiers to specify the output of numbers, for example
29 <verbatim>
30 printf "%.02f",a/b
31 </verbatim>