Perl equivilant to tail -f

jklcrash has asked for the wisdom of the Perl Monks concerning the following question:

I am currently logging an xterm session that runs the following command

tail -f "filename" | grep "foo"
[download]

I orginially tried

tail -f "filename" | grep "goo" >>./file.txt
[download]

but there is a buffer issue it doesn't start writing until roughly 800 entries are present in the file im tailing. I am just curious if any one has a perl module that is equivialent to tail -f

Comment on Perl equivilant to tail -f Select or Download Code

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Re: Perl equivilant to tail -f by runrig (Abbot) on Mar 07, 2006 at 20:00 UTC
Did you try CPAN or the faqs (or ppt)?	[reply]
Re^2: Perl equivilant to tail -f by jklcrash (Initiate) on Mar 07, 2006 at 20:10 UTC
thank you very much. FILE::TAIL works like a champ	[reply]
Re: Perl equivilant to tail -f by davidrw (Prior) on Mar 07, 2006 at 20:25 UTC
I orginially tried tail -f "filename" \| grep "goo" >>./file.txt but there is a buffer issue Just need an extra switch on the grep: `tail -f "filename" \| grep --line-buffered "goo" >>./file.txt` [download] (note that the grep manpage may incorrectly may '--line-buffering' -- details here)	[reply] [d/l]
Re: Perl equivilant to tail -f by ikegami (Patriarch) on Mar 07, 2006 at 20:10 UTC
File::ReadBackwards `use File::ReadBackwards; my $file_name = "filename"; my $fh = File::ReadBackwards->new($file_name) or die("Unable to read log file $file_name: $!"); my @lines = reverse grep /foo/, grep defined, map { scalar $fh->readline() } 1..10;` [download] Update: Oops, I wrongly assumed `-f` worked the same way as in `tar`. My snippet emulates `tail "filename" \| grep "foo"` rather than the desired `tail -f "filename" \| grep "foo"` Disregard this post.	[reply] [d/l] [select]
Re: Perl equivilant to tail -f by smokemachine (Hermit) on Mar 07, 2006 at 23:25 UTC
can be this? `perl -e 'open FILE, "<".shift; @arq=<FILE>; $a=shift; foreach(@arq[-10 +..-1]){print if /$a/} while(1){while(<FILE>){print if /$a/}}' file re +gex` [download]	[reply] [d/l]


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