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Delete a block of text delimited by blank lines when pattern is found


 
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# 1  
Old 12-15-2007
Delete a block of text delimited by blank lines when pattern is found

I have a file which contains blocks of text - each block is a multi-lines text delimited by blank lines eg.

Code:
<blank line>
several lines of text
...
pattern found on this line
several more lines of text
...
<blank line>

How do you delete the block of text (including the blank lines) when the pattern is found and leave one blank line?
# 2  
Old 12-15-2007
Something like this?

Code:
sed -n '
/^$/ b block
H
$ b block
b
:block
x
/pattern/!p' data

# 3  
Old 12-15-2007
Or:

Code:
sed '/pattern/,/^$/d' file

Regards
# 4  
Old 12-15-2007
Quote:
Originally Posted by Franklin52
Or:

Code:
sed '/pattern/,/^$/d' file

I think the OP wants something different:

Code:
$ cat data
block1
block1
block1
pattern block1
block1

block2
block2
block2
block2

block3
block3
pattern block3
block3

$ sed '/pattern/,/^$/d' data
block1
block1
block1
block2
block2
block2
block2

block3
block3

$ sed -n '
/^$/ b block
H
$ b block
b
:block
x
/pattern/!p' data

block2
block2
block2
block2

# 5  
Old 12-15-2007
Perhaps I misinterpreted the question, the OP could make it clear.

Regards
# 6  
Old 12-15-2007
Quote:
Originally Posted by radoulov
I think the OP wants something different:

...

$ sed -n '
/^$/ b block
H
$ b block
b
:block
x
/pattern/!p' data

block2
block2
block2
block2
[/code]
Yes. Thank you, Radoulov. You interpreted my question correctly. (Sorry, Franklin52 that it was none too clear).

I don't quite understand the above bit of code about the Set-Aside buffer (but I'll look it up later ...unless you or someone wants to explain for the benefit of others).

But, in any case, the final result with only lines of block2 is what I want. I will do a test run later ... before I use it in earnest on that 8 gig file at work. Thanks again.
# 7  
Old 12-15-2007
Code:
# more file
block1
block1
block1
pattern block1
block1

block2
block2
block2
block2

block3
block3
pattern block3
block3

# awk 'BEGIN{RS=""}/pattern/{next}1' file
block2
block2
block2
block2


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