Hi All,
Is there any way to monitor whether or not a named pipe has data to give, without opening it?
I want to do something like this: 
my $dbh=DBI->connect("DBI:mysql:database=pings;host=$host;mysql_connec
+t_timeout=10","$user","$password") or die "$!\n";
$sth=$dbh->prepare("LOAD DATA LOCAL INFILE 'MYFIFO' INTO TABLE $table 
+FIELDS TERMINATED BY ',' LINES TERMINATED BY '\n'") or print "$!\n".$
+dbh->{'mysql_error'};
$sth->execute() or print "$!\n".$dbh->{'mysql_error'};
$sth->finish() or print "$!\n".$dbh->{'mysql_error'};
$dbh->disconnect() or print "Trouble disconnecting! $!\n";

[download]
The problem is that if I execute the LOAD DATA INFILE whilst there is nothing writing to MYFIFO, the server times out and the operation fails. I would much rather do something like this: 
while (1) {
  if (fifo_is_ready()) {
      # Connect to database
      # LOAD DATA LOCAL INFILE 'MYFIFO' etc. etc.
      # Disconnect
   }
   else {
      sleep(2);
   }
}

[download]
But I don't know how to keep an eye on that FIFO. It gets more complicated by the fact that I need to lock tables prior to writing, but I don't want to go locking tables until I know that I'm ready to write data to them.
Any ideas?

In reply to Watching a named pipe by leighsharpe

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