Thanks everyone for your help. I finally cracked it yesterday. The trick is to open the pipe for read/write, bypass perlio and have a blocking read. The code below shows how it's done. I could possibly have moved to sockets, but pipes are as old as the hills so it should be possible to use them and on top of that the writer could be a bash script. Having said that, I did find out how to have bash write to a socket... 
# Non blocking open
open (FH, "+<", $config->{'pipe'} ) || die "Unable to open $config->{'
+pipe'}";

my $rin = '';
my $rout = '';
vec( $rin, fileno(FH), 1) = 1; # No, I have no idea either

# Loop forever.
while (1) {

    # Wait for the pipe to change status
    my $nfound = select( $rout = $rin, undef, undef, undef ); # blocki
+ng select

    my $data;
    # Non blocking select only returns a value while there is somethin
+g in the pipe
    while ( select( $rout = $rin, undef, undef, 0 ) ) {
        sysread FH, my $buf, 2048;
        $data .= $buf;
    }

    Log( { logfile => $log_file, text => 'trace: START: '. ( $data || 
+'$data no val' ) }) if TRACE;

    # 9/4/8 A request is C,DIR,1ROSE
    # Multiple requests can come through on one read ie C,FOO,1ROSEC,B
+AR,1ROSE
    for ( split /ROSE/, $data ? $data : '' ) {
        if ( /^RELOAD/ ) {
            # Reread the config file
            Log({logfile=>$log_file, text=> qq{RELOAD: Reloading confi
+g}});
            load_config();
        }
        else {
            process_input( { data => $_ } ) if $_;
        }
    }

} # while 1

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In reply to Re^2: IPC via named pipes, losing some messages by ftumsh
in thread IPC via named pipes, losing some messages by ftumsh

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