in reply to Re: Regex and writing lines in file
in thread Regex and writing lines in file

I opened the file in string context and was able to find the pattern successfully. But I could not substitute the matched pattern with required pattern 

$extra = "This is i will place after match\n.an this too";
open (my $fh, '+<', $file);
$data = <$fh>;
$data = s/(.*entry)\n([^\n]*)\n/$1\n$extra/

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The $1 is found successfully. But could not do the substitution in the file.

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Re^3: Regex and writing lines in file
by Random_Walk (Prior) on May 01, 2013 at 11:38 UTC

    You have now substituted within the $data variable. Next you need to write the contents of $data back to the file. Try adding something like this after the substitution

    # untested
seek  $fh, 0, 0; # rewind to the start of the file
print $fh $data; # Write the entire file
close $fh;

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    Of course this may not be very efficient if you have a large file to alter, but then inserting into the middle of a very big file never is. If you are frequently updating random records in a file you may need to start thinking about using a database.

    Cheers,
    R.

    Pereant, qui ante nos nostra dixerunt!
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[d/l]
[select]

      Partially worked for me. Thank you!

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