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Search a String between start and end of a block in a file

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# 1  
Old 02-22-2018
Linux Search a String between start and end of a block in a file
Hi,

I have a scenario where I want to display the output based on the pattern search between the start and end of a block in a file, we can have multiple start and end blocks in a file.
Example give below, we need to search between the start block abc and end block def in a file, after that display the block which has the word "123" in a line. I have tried this command:
Code:
awk '/^abc$/{flag=1}/^def$/{print;flag=0}flag' values.txt

, but how can we code to identify the block which has 123 word and print that entire block(refer expected out below). Please guide me in resolving this issue. Thanks all in Advance for helping!

Input file: values.txt
Code:
abc
xyz123
456
def
ghi
abc
456
def
abc
123
def

Expected Output:
Code:
abc
xyz123
456
def
abc
123
def

Last edited by Chubler_XL; 02-22-2018 at 08:23 PM.. Reason: Please use [code] and [/code] tags around data and programs
# 2  
Old 02-22-2018
store the string in a variable and test it contains 123 before printing it:

Code:
awk '
/^abc$/{flag=1;block=""}
flag{if(length(block)) block = block "\n" $0
     else block=$0 }
/^def$/ && block ~ "123" { print block }' values.txt

Last edited by Chubler_XL; 02-22-2018 at 08:34 PM.. Reason: Fixed code logic - incorrectly built block variable
# 3  
Old 02-22-2018
Code:
awk '$0~a,$0~b{l=l$0 RS;if($0~b){if(l~c)printf l;l=_}}' a="^abc$" b="^def$" c="123" values.txt

# 4  
Old 02-22-2018
Linux
Quote:
Originally Posted by Chubler_XL
store the string in a variable and test it contains 123 before printing it:

Code:
awk '
/^abc$/{flag=1;block=""}
flag{if(length(block)) block = block "\n" $0
     else block=$0 }
/^def$/ && block ~ "123" { print block }' values.txt

Quote:
Thanks for the code snippetSmilie, And can we search multiple strings like either "123" or "456" if it didn't find 123 then it has to check for 456. How can we include "OR" condition?Smilie
---------- Post updated at 07:37 PM ---------- Previous update was at 07:15 PM ----------

Quote:
Originally Posted by rdrtx1
Code:
awk '$0~a,$0~b{l=l$0 RS;if($0~b){if(l~c)printf l;l=_}}' a="^abc$" b="^def$" c="123" values.txt

Quote:
I got an error "ran out of here" while running for the original file
# 5  
Old 02-23-2018
I think the flag should control a bit more. For example a further abc within a block should be ignored. Dito a further def outside the block.
The logical OR is ||
Code:
awk '{
  if (flag==0) {
    if (/^abc$/) {
      flag=1; block=$0
    }
  } else {
    block=(block RS $0)
    if (/^def$/) {
      flag=0; if (block ~ "123" || block ~ "456") print block
    }
  }
}' values.txt

Last edited by MadeInGermany; 02-23-2018 at 05:09 PM.. Reason: RS not FS
# 6  
Old 02-23-2018
You can use sed for this task.
Code:
start='abc'
end='def'
search1='123'
search2='456'
sed '/^'"${start}"'/!d;:A;N;/\n'"${end}"'/!bA;/'"${search1}"'/bB;/'"${search2}"'/!d;:B' infile

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