Question

I am running a website where we are serving a large amount of files from a folder mounted over Fuse (cloudfuse – a Rackspace Cloudfiles container), it works wonderfully most of the time however every now and again the Fuse connection stalls and all my Apache processes hang waiting for a file_exists() function to return.

My question, is there anyway to set a timeout for a specific function or to use another function to check if the file exists but return with false if function takes longer than x seconds?

Answer 1

I think file_exists() is only simple function, and is not intended for such operations.

Workaround #1 (quite elegant)

• make a batch file which is checking is file exists
• use system() function to execute your batch file and parse result

Workaround #2 (simpler, not elegant at all)

• make a script file_exists.php?file=… returning string “TRUE” or “FALSE” if file $_GET[‘file’] exists. Set time_limit in this file to 1 second.
• get results using fsockopen(‘http://localhost/file_exists.php?file=’.$file, …, …, 2) and parse results. (empty or FALSE = file doesn’t exists). 2 is fsockopen’s timeout. You can use system(‘/usr/bin/php /path/to/your/script.php’) as well