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Sed / awk - print text between patterns overlaid on multiple lines

I am new to scripting and tried to learn how to extract any text that exists between two different templates. However, I still cannot figure out how to extract text between two patterns in the following scenario:

If I have an input file:

Hi I would like to print text between these patterns

and the expected output is as follows:

 I would like to print text between these

i.e. my first search pattern is “Hello” and skip this pattern, but type everything that exists on the same line as the corresponding pattern. My second search pattern is “patterns,” and I would like to completely avoid printing this line or any lines outside it.

I tried the following:

 sed -n '/Hi/,/patterns/p' test.txt

[exit]

 Hi I would like to print text between these patterns

Next I tried:

 `awk ' /'"Hi"'/ {flag=1;next} /'"pattern"'/{flag=0} flag { print }'` test.txt

[exit]

 to print text between these

Can someone help me in deciding how to achieve this? thanks in advance

+8
bash awk sed
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4 answers

You have the right idea, a mini-state machine in awk , but you need small mods according to the following transcript:

 pax> echo 'Hi I would like to print text between these patterns ' | awk ' /patterns/ { echo = 0 } /Hi / { gsub("^.*Hi ", "", $0); echo = 1 } { if (echo == 1) { print } }'

Or in a concise form:

 awk '/patterns/{e=0}/Hi /{gsub("^.*Hi ","",$0);e=1}{if(e==1){print}}'

Result:

 I would like to print text between these

upon request.

How it works is as follows. Initially, the variable echo 0 means that there will be no echo.

Each line is checked in turn. If it contains patterns , the echo is disabled.

If it contains Hi followed by a space, the echo is turned on and gsub used to change the line to get rid of everything to Hi .

Then regardless of whether the line is on (possibly changed) when the echo flag is on.

Boundary cases will now appear, such as:

  • strings containing two occurrences of Hi ; or
  • strings containing something in front of patterns .

You did not indicate how they should be handled so that I would not worry, but the basic concept should be the same.

+6
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Updated solution for deleting strings "patterns":

 $ sed -n '/^Hi/,/patterns/{s/^Hi //;/^patterns/d;p;}' file I would like to print text between these
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This may work for you (GNU sed):

 sed '/Hi /!d;s//\n/;s/.*\n//;ta;:a;s/patterns.*$//;tb;$!{n;ba};:b;/^$/d' file
+2
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Just set flag (f) when you find + replace Hi at the beginning of the line, clear it when you find patterns, then call default printing when setting the flag:

 $ awk 'sub(/^Hi /,""){f=1} /patterns/{f=0} f' file I would like to print text between these
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