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)

In reply to Re: Perl equivilant to tail -f by davidrw
in thread Perl equivilant to tail -f by jklcrash

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