In some code I am writing, I have a logging subroutine which directs messages with a time stamp and process ID to a file. If a file name is not passed to the subroutine, the message is to be directed instead to STDERR. While I got this code working as desired through a bit of reading through redirecting STDERR, then back again and perlfunc:open, I am wondering if there is a cleaner way to implement this solution? The current version of my subroutine code follows: 

sub write_logfile ($$) {
    use Time::HiRes 'time';
    my ($file, $message) = @_;
    chomp($message);
    if (defined($file)) {
        open OLDERR, ">&STDERR";
        open STDERR, ">>$file";
        flock STDERR, 8;
        print OLDERR "";
    };
    print STDERR time, " [", $$, "] ", $message, "\n";
    if (defined($file)) {
        close STDERR;
        open STDERR, ">&OLDERR";
    };
};

[download]

The duplication and restoration of STDERR however seems messy and I'm wondering if TAMBWTDI (there's a much better way to do it).

Note: The print OLDERR ""; line is there to prevent the 'Name "main::OLDERR" used only once: possible typo at blah.perl line 162.' error otherwise generated under -w as per melguin's node here.

 

Ooohhh, Rob no beer function well without!

In reply to Cleaner redirection of STDERR by rob_au

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