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unixawksedtext-processing

Loop and process over blocks of lines between two patterns in awk?

This is actually a continued version of thisquestion:

I have a file

1
2
PAT1
3    - first block
4
PAT2
5
6
PAT1
7    - second block
PAT2
8
9
PAT1
10    - third block

and I use awk '/PAT1/{flag=1; next} /PAT2/{flag=0} flag' to extract the blocks of lines.

Extracting them works ok, but I'm trying to iterate over these blooks in a block-by-block fashion and do some processing with each block (e.g. save to file, process with other scripts etc.).

How can I construct such a loop?

Solution

  • Problem is not very clear but you may do something like this:

    awk '/PAT1/ {
   flag = 1
   ++n
   s = ""
   next
}
/PAT2/ {
   flag = 0
   printf "Processing record # %d =>\n%s", n, s
}
flag {
   s = s $0 ORS
}' file

    Processing record # 1 =>
3    - first block
4
Processing record # 2 =>
7    - second block