You either have to track that explicitly, with some sort of counter, possibly in your printing loop, or you need a little smoke and mirrors magic.

If you are a proponent of magic, you can tie your filehandle to a class that keeps track of the number of lines printed for you. You could then query the filehandle object to determine if the max number of lines has been reached, or if it's nearing, etc.

See tie, and perltie for details on tieing filehandles. The details are a little obscure at first, but once you get the hang of it you can create some interesting spells.

IO::ScalarArray / IO::Lines are fun.

You may need Text::Wrap as well, depending on your line lengths.

If you can't count the lines before calling print, it should be feasible to create a tied handle class that counts them as they are printed.

The more I think about it, the more I think that for most needs it's probably best to just count newline characters immediately prior to printing:

$count += $print_string =~ tr/\n//;
print OUT $print_string;
[download]

...why get tricky with something so easy, right?

Yes after looking at the project it was much simpler to just count the newlines before each print, and that is what I wound up doing. Thanks for the suggesstions and help. Here is a sample of what i wound up doing as far as the same FILEHANDLE, different file goes:


$filename = "MyJScript01.txt";
push(@filenames,$filename);
$filenumber = 1; #variable to track the filenames format: MyJscript#.t
+xt where # is a number
open (OUT,">$filename");


print OUT "<script language='JavaScript'>\n";
print OUT "function whichMapper(obj){\n";
print OUT "if(obj.selectLSO.selectedIndex == 1){\n";
$lineCounter = 3; #Track the number of newlines printed to the JS file

(other code with many prints each line incrementing $linecounter)...

    if($lineCounter > 1000){
        close OUT;
        $filenumber += 1;
        $filename = "MyJScript0".$filenumber.".txt";
        push(@filenames,$filename);
        open (OUT,">$filename");
        $lineCounter = 0;
    }
    
}

    print OUT "}\n";
    print OUT "</script>\n";
close OUT;
(at the end I do stuff with the files created)...
[download]

This is a snippet from a larger program, but basically what I was doing was creating a javascript file based on some data in a db. The file was being included into a dynamic webpage. The file apparently got too large an cause a buffer overrun in the include directive of the web server we use. so I just decided to break the file up into smaller files and include them in order. Wound up working fine.

my $max_line_count = $whatever;
my $file_count = my $line_count = 0;
my $outfh;

sub printAndCount
{
    local $_ = shift;
    my $lines2print = tr/\n/\n/;  # simple way to count \n's
    if ( $file_count == 0 or 
         $line_count + $lines2print > $max_line_count )
    {
        close $outfh if ( $file_count );
        open $outfh, sprintf( ">track%03d.txt", ++$file_count ) or die
+ "open failed: $!";
    }
    print $outfh;
    $line_count += $lines2print;
}
[download]

The end goal is that when a cetain number of lines is reached i want to close the file handle, and open a new one with the same name that points to a different file.