Unique file ID

[arkum]

Howdy,

What is the most sensible way of giving any file which I try to save (which doesn't already exist) a unique name? Should I append the date to a consistant filename?

[ToonMariner]

a timestamp may be more usefull - or even better micro time. If multiple users can upload then just to be really careful perhaps use their user_id and the micro-time to name the file.

[arkum]

Hi ToonMariner,

Thanks for replying, but can you explain how I would append a timestamp? I don't have to worry about multiple users, so it can be very simple.


Thanks

[Orio]

Using tempnam(), give this a try:

[code]<?php

function unique_name()
{
$name = tempnam("/", "");
if($name !== FALSE)
{
unlink($name);
return $name;
}
else
return FALSE;
}

?>[/code]

Orio.

[arkum]

Hi Orio,

Just got sucked into your avatar animation for about 5 minutes(years?)...

Don't quite get the code. You are creating a file, then deleteing it, then returning it?

And what do the ("/", "") mean?

Thanks

[Orio]

Read about [url=http://www.php.net/tempnam]tempnam()[/url]. Here's what it does, basically:
It creates a file within the given folder (I've set it "/" - the current folder) with the prefix given (I've set it to "" - no prefix). This new file has a name that is unique- there's no chance for over writing. This function returns the name of that file created, so you can use it.

Back to my function- If an error occurs the function returns FALSE, and if everything is ok the unique filename is being returned. I deleted the file created by tempnam, because there's no need for it, you just want the name, right?

Orio.