Add variable in php file with inside array using fwrite()?

Question

I have problems to add variable in php file with inside array using fwrite.

My php file has an array and is like this:

<?php 
  $array48= array (
   0 => 
   array (
     0 => '2019-04-24-1248326-1313',
     1 => 1556110847000,
     2 => 30.6647,
     3 => 71.387200000000007,
     4 => 3.999999999999999,
     5 => 51,
     6 => 'O',
     7 => 13,
     8 => 0,
   )
 )

I want to add variable at first of file:

$fp_due_min_fa = fopen('../file.php', 'r+');
fwrite($fp_due_min_fa, '<?php ' . "\n" . '$id = ' . $id_terr . ';' . "\n");
fclose($fp_due_min_fa);

but after this code the php file is like this:

<?php 
  $id = 123456;
  556110847000,
     2 => 30.6647,
     3 => 71.387200000000007,
     4 => 3.999999999999999,
     5 => 51,
     6 => 'O',
     7 => 13,
     8 => 0,
   )
 )

The array is break...

I would to have this output:

<?php 
  $id = 123456;
  $array48= array (
   0 => 
   array (
     0 => '2019-04-24-1248326-1313',
     1 => 1556110847000,
     2 => 30.6647,
     3 => 71.387200000000007,
     4 => 3.999999999999999,
     5 => 51,
     6 => 'O',
     7 => 13,
     8 => 0,
   )
 )

Why I have this mistake?

Answer 1

The overall design looks bad, but in general just read, concatenate and write to pre-pend to the beginning. So as not to have to strip out the opening PHP tag, just open and close the tags:

$output = "<?php \$id = $id_terr; ?>\n";
$file   = file_get_contents('../file.php');
file_put_contents('../file.php', $output.$file);

Or to append (assuming there is no closing PHP tag as shown), simply:

file_put_contents('../file.php', "\n\$id = $id_terr;\n", FILE_APPEND);