#!/usr/bin/perl -w

use Time::HiRes;

$SIG{"ALRM"}=\&sigAlarm;

my $interval=1;
my $uInterval=$interval*10**6;
Time::HiRes::ualarm($uInterval, $uInterval);

my $logname='xyz';
open TAIL, "tail -f $logname|" or die "couldn't open $logname";
while (1)
{
  while(1)
  {
    if (eof(TAIL))
    {
      printf "EOF: %d\n", eof(TAIL);
      $line=<TAIL>;
      next;
    }

    last    if !($line=<TAIL>);
    print $line;
  }
  print "Fell through...\n";
}

sub sigAlarm
{
  print "alarm\n";
}