You want to take a look at File::Tail, which implements methods to follow a file.

The documentation mentions several ways how you can use the filehandle returned by File::Tail, you can either use it as an IO handle, complete with select() support, or use the read() method, which tries to have near 0% CPU usage and will return whenever a new line is available.

-Blake

Why not take a slightly different approach. Constantly read the file, but only process complete lines. Something like this:

my $buff;
my $data;

while (1) {
  if (read(MUFFINLOG, $buf, 1024)) {
    $data .= $buf;
    while ($data =~ /\n/) {
      my $line;
      ($line, $data) = split /\n/, $data, 2;
      # process the line of data that is in $line
    }
  }
}
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Perl Training in the UK <http://www.iterative-software.com>

I believe you need a seek( MUFFINLOG, 0, 1 ); in there to reset the eof... otherwise you won't get newly appended data...

                - Ant
                - Some of my best work - Fish Dinner

That sounds sensible. Good catch.

Of course, the best solution would probably to use File::Tail as others have suggested.

--
<http://www.dave.org.uk>

Perl Training in the UK <http://www.iterative-software.com>

me = /s27 ... i get the newly appended data (don't know why ;) - i think i'll use the TAIL thing... sounds good to me. thx alot for all the support.

A simple method is to use IO::Select to watch over the handle. The example below watches STDIN and waits for 5 seconds for a read before passing on.

By playing with parameters you can change the wait time, or make the code wait permanently. Also, by using IO::Handle or the like, you can read in individual characters, instead of whole lines.

#!/usr/bin/perl

use IO::Select;

my $select = IO::Select->new();

$select->add(\*STDIN);
my @ready;

while(1) {
        if(@ready = $select->can_read(5)) {
                foreach (@ready) {
                        my $line = <$_>;
                        print "Read $line\n";
                }
        } else {
                print "5 seconds passed without a read\n";
        }

}
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$japh->{'Caillte'} = $me;

push(@Zeile,$_);
&ZeilenAnalyse;
# and other related code
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