simulating tail -f in Perl

Question

As per solution provided in perldoc , I am trying to emulate tail -f but it's not working as expected. The below code could print all lines first time but not the newly lines appended. Could you please elaborate if I am missing any thing here.

#!/usr/bin/perl
open (LOGFILE, "aa") or die "could not open file reason $! \n";

for (;;)
{
        seek(LOGFILE,0,1);  ### clear OF condition        
        for ($curpos = tell(LOGFILE); <LOGFILE>; $curpos = tell(LOGFILE)) 
        {
                print "$_ \n";
        }

        sleep 1;
        seek(LOGFILE,$curpos,0); ### Setting cursor at the EOF
}

Answer 1

works fine for me. How are you updating "aa" ? You wont see the data immediately if it is a buffered write to "aa" . can you try the following in a different terminal and check whether you are seeing any update.

while ( 1 )
echo "test" >> aa
end

If you are using perl to update aa , check this section on buffering and how to disable.