Create a php file of specified size

Question

How to create a file of a given size (regardless of content) in PHP?

I have to create a file larger than 1GB. Maximum approximately 4-10GB

Answer 1

If the contents of the file are not relevant, just populate it - but make sure you don't generate variables that are too large to hold in memory:

<?php
$fh = fopen("somefile", 'w');
$size = 1024 * 1024 * 10; // 10mb
$chunk = 1024;
while ($size > 0) {
   fputs($fh, str_pad('', min($chunk,$size)));
   $size -= $chunk;
}
fclose($fh);

If the file must be read by something else - then how you do it depends on what else needs to read it.

C.

Answer 2

You can use fopen and fseek

define('SIZE',100); // size of the file to be created.
$fp = fopen('somefile.txt', 'w'); // open in write mode.
fseek($fp, SIZE-1,SEEK_CUR); // seek to SIZE-1
fwrite($fp,'a'); // write a dummy char at SIZE position
fclose($fp); // close the file.

When executing:

$ php a.php

$ wc somefile.txt
  0   1 100 somefile.txt
$