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[QUESTION] cannot open "tail -f"

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From:
Jovi Zhang
Date:
December 22, 2010 00:41
Subject:
[QUESTION] cannot open "tail -f"
Message ID:
AANLkTikD+Hq1vFa5ZFBmtg2nXxyky1z1+SJ-3fyVn_UG@mail.gmail.com
Hi,
    I use a very simple perl script like below, I don't know why this
happen, so anybody can give me some clue on this?
##############################################################################
#! /usr/bin/perl -w

use strict;

open(my $log, "tail -f /srv/Log/log/syslog | grep semper_prb1x |");

# This can work:
#open(my $log, "cat /srv/Log/log/syslog | grep semper_prb1x |");

while (my $line = <$log>) {
       print "$line";
}

# So why "tail -f" can not work?
##############################################################################
# perl --version

This is perl, v5.8.7 built for x86_64-wrs-linux-gnu
(with 1 registered patch, see perl -V for more detail)

Copyright 1987-2005, Larry Wall

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