I'm learning (or trying to learn) how to work with filehandles passed along through returns and params.

I believe I have the fileopen and return working. At least is seems to be working.

The part I'm messing up on is the file locking part.

From flock manpage: 

sub lock {
    flock(MBOX,LOCK_EX);
      # and, in case someone appended
      # while we were waiting...
      seek(MBOX, 0, 2);
}

sub unlock {
    flock(MBOX,LOCK_UN);
}

open(MBOX, ">>/usr/spool/mail/$ENV{'USER'}")
    or die "Can't open mailbox: $!";

lock();
print MBOX $msg,"\n\n";
unlock();

[download]
Below was my attempt at making this work. If a kind hearted monk could help unscramble this I'd appreciate it. 
sub fileopen {
    my($filename) = @_;
    local *MW;

    my($openokay) = open(MW,"+<$filename"); 

    if (!$openokay) {
        return 0;
    }

    lock(*MW);  

    seek(MW,0,0);
    return *MW;
}

sub lock {
    my($nick) = @_;
    flock({$nick},LOCK_EX);
      # and, in case someone appended
      # while we were waiting...
      seek({$nick}, 0, 2);
}

sub unlock {
    my($nick) = @_;
    flock({$nick},LOCK_UN);
}

[download]
Thanks in advance. Claude

In reply to flock with anonymous filehandle by Xxaxx

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