I use this code to upload files via CGI, I know this works.

my $mode = "0755";
    
my $localfile = "$uploaddir/$filename";

    # open a new file and transfer bit by bit from what's in the buffe
+r
    open( SAVED, ">>$localfile" );  
    while ( my $bytesread = read( $remotefile, my $buffer, 1024 ) ) {
        print SAVED $buffer;
    }
    close SAVED;

    chmod $mode, "$localfile";        # or die "can't chmod: $!";
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Do you think this will work for what the OP wanted? It tried hacking it to open two files and read from the original and write to the new one.

my $mode = "0755";
    
my $localfile = "$uploaddir/$filename";
my $newfile   = "$uploaddir2/$filename";

    # open original file
    open( SAVED, ">>$localfile" );  

    # open new file
    open( NEW, ">$newfile" );

    # write the original file to the new filename
    while ( my $bytesread = read( $remotefile, my $buffer, 1024 ) ) {
        print NEW $buffer;
    }
    close(SAVED);
    close(NEW);

    chmod $mode, "$newfile";        # or die "can't chmod: $!";
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