I was going to write some code to tail a log file and detect when it rolled and then close/reopen it. Then I saw a reference to File::Tail and it sounded like just what I want. So I thought I'd try something very simple. I literally copied the sample usage script, pointed it to a file called /tmp/xxx with a few lines in it and nothing happens! I tried to echo some additional lines to the file they're not reported either. Could there be some versioning thing going on? I'm running perl 5.8.8 and File::Tail 0.99.3. 
#!/usr/bin/perl -w

use File::Tail;
$file=File::Tail->new("/tmp/xxx");
while (defined($line=$file->read)) {
    print "$line";
}

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When I run it there is no output. I even put a print right after the first call to make sure it gets to the while line and it does. Any ideas what I could try to see what's wrong?

I even tried eliminating the while and simply doing the read since I know there's something in the file: 

use File::Tail;
$file=File::Tail->new("/tmp/xxx");
print "opened\n";
$line=$file->read;
print "after read\n";
print "$line";

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and when I run it, it seems to be hanging on the read. The doc says you can pass it a non-zero value for debug so I tried 99 and got nothing. It feels like the file isn't getting opened but I have no ideas why.

Finally I tried getting even more creative with more instrumentation as well as some error handling. 

use File::Tail;
$file=File::Tail->new(name=>"/tmp/xxx", debug=>99, interval=>1, maxint
+erval=>1) or print "ERROR1: $!\n";
print "ERROR2: $!\n";
print "opened\n";
$line=$file->read;
print "after read\n";
print "$line";

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It now looks like $! is getting set to "Inappropriate ioctl for device", but only when I report it with ERROR2 and not ERROR1. Is that message even real? In other words the constructor doesn't seem to be failing. I'm real confused by what I'm seeing.

-mark

In reply to I can't get the sample code for File::Tail to read my file by markseger

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