How to append to file using ob_start

Question

I have looked for quite a while now, to see if it's possible to "append" to a file if using ob_start with PHP.

I have tried the following but did not work. Any way of achieving this?

<?php

$cacheFile = 'file.txt';

if ( (file_exists($cacheFile)) && ((fileatime($cacheFile) + 600) > time()) )
{
$content = file_get_contents($cacheFile);
echo $content;
} else
{
ob_start();
// write content
echo '<h1>Hello world</h1>';
$content = ob_get_contents();
ob_end_clean();
file_put_contents($cacheFile,$content,'a+'); // I added the a+
echo $content;
}
?>

I borrowed the above example from another post on S.O.

Answer 1

To append using file_put_contents() you can simply pass FILE_APPEND as the third argument:

file_put_contents($cacheFile, $content, FILE_APPEND);

It can also be used to apply file locking using the binary OR operator, e.g. FILE_APPEND | LOCK_EX.

Answer 2

file_put_contents doesn't work that way. To append, you need to use fopen, fwrite and fclose manually.

$file = fopen($cacheFile, 'a+');
fwrite($file, $content);
fclose($file);