PHP rename files, starting with special name? - php

Question

i wanted to rename files from databse. so..i wrote bellow.
it works fine except for names with long length int.
(ex: bartmp_9404865346.jpg does not work but bartmp_585558.jpg is working)
$subject = '[img]http://www.example.org/users/uploads/bartmp_9404865346.jpg[/img]
Hello world
[img]http://www.example.org/users/uploads/bartmp_585558.jpg[/img]';
preg_match_all('/\[img\](.*?)\[\/img\]/', $subject, $files);
foreach ($files[1] as $file) {
$n = sscanf($file, "http://www.example.org/users/uploads/bartmp_%d.jpg");
$refile = sprintf("http://www.example.org/users/uploads/mybar_%d.jpg", $n[0]);
rename($file, $refile);
}
can you give me any alter way to do this or a little hint to modify this.
thanks.

Answer 1

The %d format specifier only accepts numbers that would fit in an integer (depending on the platform that would be 2^31 or 2^63); without losing precision, in this case, a regular expression may work better:
if (preg_match('#^http://www.example.org/users/uploads/bartmp_(\d+)\.jpg$#', $file, $matches)) {
$refile = sprintf('http://www.example.org/users/uploads/mybar_%s.jpg', $matches[1]);
rename($file, $refile);
}
The above expression matches only digits but stores the match as a string value, so it won't lose numeric precision.

Answer 2

You are using %d for decimal which seems superficially correct:
$n = sscanf($file, "http://www.example.org/users/uploads/bartmp_%d.jpg");
$refile = sprintf("http://www.example.org/users/uploads/mybar_%d.jpg", $n[0]);
The issue is the max numerical value in PHP—and other languages compiled as 32-bit—is 2147483647 so 9404865346 won’t fly. Instead you should look to extract the value as a string instead like this:
$n = sscanf($file, "http://www.example.org/users/uploads/bartmp_%s.jpg");
$refile = sprintf("http://www.example.org/users/uploads/mybar_%s", $n[0]);