in reply to Re: How to print 5 lines below after a regex match
in thread How to print 5 lines below after a regex match

Thanks I see the lines posted below my match. One last thing which I should have included, how do also print the matched line as well. Many thanks

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Re^3: How to print 5 lines below after a regex match
by poj (Abbot) on Feb 24, 2016 at 20:43 UTC

    Set the flag first then print

    use strict;
my $flag = 0;
my $few = shift || 3;

while (<DATA>) { 
  $flag = $few if (/Update certificate/);
  print $_ if ($flag-- > 0);
}

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    poj
[reply]
[d/l]
      It really depends on what the OP really needs, but there is a danger of $flag being reset while it is reading the next "few" lines, if the regex matches again. Perhaps something like this: 
      use strict;
my $few = shift || 3;
while (<DATA>) { 
  if (/Update certificate/) {
    print $_;
    print scalar <DATA> for 1..$few;
  }
}

      [download]
      Or possibly for 1..$few-1;, depending on whether $few includes the matching line or not.
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