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Re^3: Watch log for string (tail -f)

by BrowserUk (Pope)
on Oct 11, 2012 at 20:45 UTC ( #998543=note: print w/replies, xml ) Need Help??

in reply to Re^2: Watch log for string (tail -f)
in thread Watch log for string (tail -f)

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.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

RIP Neil Armstrong

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Re^4: Watch log for string (tail -f)
by bimleshsharma (Beadle) on Oct 12, 2012 at 07:39 UTC

    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");
Re^4: Watch log for string (tail -f)
by Skootaman (Novice) on Sep 30, 2013 at 11:44 UTC
    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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