Delete/Remove Last 5 Lines from Text file

[defonic]

Extremely new here and to PHP and I have exhausted my newbie resources and my brain on this one.  :'(

 

Concept: Cron Job to INSERT 5 lines per hour (Not the whole list at once)

[*]Script to read a pipe delimited text file (about 5k Lines)

[*]Open File Get last (bottom) 5 lines of file, ignore the rest

[*]Insert those 5 lines into my database

[*]Open File, Remove last (bottom) 5 lines

 

I am able to do parts 1-3 but not part 4 (removing last 5 lines) Please help me!

 

$data = array_slice(file('data.txt'), -5);
foreach($data as $value)
{
  $fields=explode("|",$value);
  $num=count($fields);
  for ($n=0;$n<$num;$n++)
  {
    $null="";
    print ($n==0) ? "Importing Video...<BR>" : $null;
  }

// Insert into tmpvideos table here
include("includes/config.php");
            $last_id_result = @mysql_query( @"SELECT ext_id FROM tmpvideos ORDER BY ext_id+0 DESC, id DESC" );
            if ( 0 < @mysql_num_rows( $last_id_result ) )
            {
                $last_id = @mysql_result( $last_id_result, 0, "ext_id" ) + 1;
            }
            else
            {
                $last_id = "1";
            }


            copy($fields[3], "thumbs/ex_".$last_id.".jpg" );
            $fields[3] = "thumbs/ex_".$last_id.".jpg";

set_time_limit(0);
mysql_query("INSERT into tmpvideos (id, ext_id, title, description, duration, category, date_added, thumb, video, views, rating, votes, status)
VALUES ('','".$last_id."','$fields[0]','$fields[1]','$fields[5]','$fields[6]',NOW(),'$fields[3]','$fields[2]','','','','1')");

}

 

I understand the 'concept' but am unable to grasp the code! I have tried many snippets and really need help.

[WebStyles]

if you know how to get the last five lines, do the reverse, get all the lines except the last five, and write the whole thing to the file (replacing all content)

[defonic]

Every time I try I end up removing everything except the last 5 lines. 

[WebStyles]

should be something like:

$data = array_slice(file('data.txt'), 0, -5, true));

[defonic]

should be something like:

$data = array_slice(file('data.txt'), 0, -5, true));

 

With your help I solved it, Thank you! 

 

$alines=file('data.txt');
$dlines=array_slice($alines,0, -5);
$fileContents=implode($dlines);
$fp=fopen('data.txt','w+');
fwrite($fp,$fileContents);
fclose($fp);