in reply to Tail a rapidly changing file

I would just write my own code, it's pretty easy: 

#!/usr/bin/perl
use strict;
use warnings;
use Fcntl qw/:seek/;

my $file='my.log';

# position to end
open(FILE,$file) || die "$file: $!";
seek(FILE,0,SEEK_END) || die "Seek: $!";
my $pos=tell(FILE);
close FILE;

while(1) {
   sleep(5*60);   # every 5 minutes
   open(FILE,$file) || die "$file: $!";
   seek(FILE,$pos,SEEK_SET) || die "Seek: $!";
   while (<FILE>) {
      #  do something with $_ lines
   }
   $pos=tell(FILE);   # update
   close FILE;
}

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Send it the kill signal when you're done with it, or you could get fancy by adding code to abort when it sees something or other.

HTH,
SSF

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Re^2: Tail a rapidly changing file
by matze77 (Friar) on Jan 16, 2010 at 15:09 UTC

    Hello!
    I dont know what use Fcntl qw/:seek/; accomplishes if someone got the time maybe he/she could explain?
    Thanks
    MH

[reply]
[d/l]
      I dont know what use Fcntl qw/:seek/; accomplishes ...

      It imports the constants SEEK_SET SEEK_CUR SEEK_END.

      Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
      "Science is about questioning the status quo. Questioning authority".
      In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
[d/l]

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