sed multiline replace

sed multiline
rbawaskar picture rbawaskar · Aug 3, 2009 · Viewed 16.9k times · Source

this is my sample text file :

asdas
//<<<TAG
this should be removed
//TAG>>>
this should be there
//<<<TAG
T
>
asd
asd
//TAG>>>

for which i want o/p as :

asdas

this should be there

Basically i m trying to find lines between "//<<>>" (including these lines too) and delete them.

I tried using sed

sed -n '1h;1!H;${;g;s///<<]*TAG>>>//g;p;}' < test.txt

But some how it did not produced correct output. The second tag which contained ">" symbol failed in regex. Not sure where i m going wrong?

Any idea how to do it ?

Answer

William Pursell picture William Pursell · Aug 3, 2009

If you are trying to delete lines with the literal text 'TAG', try:

sed '/\/\/<<<TAG/,/\/\/TAG>>>/d'

From your comments, it appears that TAG may not be literal, in which case:

sed '/^\/\/<</,/^\/\/.*>>/d'

This can be simplified by using a different delimiter:

sed '@^//<<<@,@^//.*>>>@d'

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