If I understood correctly- 

perl -pi.bak -e 's#
:dir=\.\./(somthing.cpp)#
:dir=\.\./mainDir/sudir/$1#' file

[download]

If you want to do this as part of a larger script take a look at Tie::File or Editing Files In Place

Update:added :dir=

Update:eeek! I just noticed that this node is awfully like this one have I failed dws's homework appeal?

--
Until you've lost your reputation, you never realize what a burden it was or what freedom really is. -Margaret Mitchell

In reply to Re: changing name within a file by greenFox
in thread changing name within a file by DS

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