problem with printing to begining of file

[calabama]

Hello,
I am trying to make this sub write either to the begining or the end of the file. The variable $placement indicates which process will execute. This variable is then used in the if statement inside the sub routine below.

The print statement print DB "$record\n";
prints to the end of the file. How do I print to the top of the file.

Thanks

sub add_record {
  $key   = time();
  $record=$key;
  $placement = $q->param('placement');

  foreach $field (@fields){
    ${$field}  = $q->param($field);
    ${$field}  = filter(${$field});
    $record   .= "\::${$field}";
  }

  unless (-e $database){
    open (DB, ">$database") || die "Error creating database.  $!\n";
  } else {
    open (DB, ">>$database") || die "Error opening database.  $!\n";
  }
   flock DB, $EXCLUSIVE;
   seek DB, 0, 2;
       
if ($placement eq "beg") {
} else {  print DB "$record\n";
}

   flock DB, $UNLOCK;
  close(DB);
} 
# End of add_record subroutine.

In the begining
Let us first assume that there was nothing to begin with.

 

[mtek13]

You opened a file for appending
so automatically it will be adding to the end.
If you want to add to the top of the file try to read the file first and put it in an array starting from 1, then
in position 0 of your array. After that you can output to the file.

Mtek13

 

[Coderifous]

Or if the file is too large to read into memory, you could do something like this:

###########################################

$filepath = "/path/to/file";
$addition = "Some wonderful string here";

addToTop($filepath, $addition) || die "Couldn't add to top";

sub addToTop {
    my $filepath = shift;
    my $string = shift;
    my $bak = ".addToTopBakup";

    rename($filepath, $filepath.$bak) || return 0;
    open( FILE, $filepath.$bak ) || return 0;
    open( UPDATEDFILE, ">".$filepath ) || return 0;

    print UPDATEDFILE $string;
    while(<FILE>){ print UPDATEDFILE $_; }

    close FILE;
    close UPDATEDFILE;

    unlink $filepath.$bak;
}
###########################################

And that's all folks.

--jim