Tuesday, July 5, 2011

does sed support lookahead or lookbehind on Linux?

after investigating for a while, finally I found sed does not support lookahead or lookbehind assertions.

Based on http://sed.sourceforge.net/sedfaq6.html, the modified sed, which is named as ssed, can support it in its Perl mode.
at

3 comments:

  1. T_XOctober 12, 2012 at 7:54 PM

    Aiy, had been trying to do a negative look-ahead as described here: http://stackoverflow.com/questions/406230/regular-expression-to-match-string-not-containing-a-word

    And I failed miserably with sed. Thanks to your post I tried 'ssed -R' and that worked right away - thanks a lot!

    ReplyDelete
  2. AnonymousSeptember 13, 2013 at 9:17 AM

    Thanks from Dortmund, Germany.
    Solved my problem.

    ReplyDelete
  3. UnknownJuly 26, 2015 at 12:21 PM

    Linux : positive and negative sides

    ReplyDelete