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in reply to Re: Watch log for string (tail -f)
in thread Watch log for string (tail -f)

lol, yes it keep going and going and going. Any ideas about how to make it exit once 3 occurrences are cough in the tail -f command?

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Re^3: Watch log for string (tail -f)
by BrowserUk (Patriarch) on Oct 11, 2012 at 20:45 UTC

    tail -f doesn't end until you interrupt it. Try something like this: 

    #! perl -slw
use strict;

my $pid = open TAIL, '-|', 'tail -f theLog' or die $!;
my @matches;
while( @matched <3 and defined( $_ = <TAIL> ) ) {
      push @matches, $_ if /the search term/;
}

kill 2, $pid;

## do something with the 3 lines in @matches.

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[reply]
[d/l]
[select]

      Try this, May this will help

      use File::Tail;

sub reading_updated_file
{
    my $path=shift;
    my $count=0;
    my $file=File::Tail->new($path);
    while(defined (my $read=$file->read))
    {
      if($read =~ /string_to_match/)
        { 
          $count++;
           last if $count ==3;
          
        }

    print "here doing rest statements";
    }

    
}
&reading_updated_file("path of file_to tail");

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[reply]
[d/l]
      This just really helped me. Note that @matches is declared but is interchangeably used as @matched, apart from that, this is really useful - thanks :)
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