chunk_split
Description
string chunk_split ( string body [, int chunklen [, string end]])
Can be used to split a string into smaller chunks which is useful for e.g. converting base64_encode output to match RFC 2045 semantics. It inserts
end
(defaults to "\r\n") every
chunklen
characters (defaults to 76). It returns the new string leaving the original string untouched. 
Example 1. chunk_split() example
<?php
// format $data using RFC 2045 semantics
$new_string = chunk_split(base64_encode($data));
?>
See also str_split(), explode(), split(), wordwrap() and RFC 2045.
