time limit function execution in PHP or anything else

PHP doesn't provide a general way to timeout a function. But many components where this problem is common let you define a timeout.

Examples:

• The HTTP Stream Wrapper allows you to specify a timeout option:

  file_get_contents('http://example.com', false, stream_context_create(    array('http' => array('timeout' => 10 /* seconds */))));

• PDO (database abstraction layer) allows you to set a timeout using the PDO::ATTR_TIMEOUT attribute (note that this attribute may mean different things with different database drivers):

  $pdo->setAttribute(PDO::ATTR_TIMEOUT, 10 /* seconds */);

• You can set a connection timeout when using FTP:

  $ftp = ftp_connect('example.com', 21, 10 /* seconds */)

Similarly all other extensions that access potentially remote resources will provide such timeout parameters or options.

In PHP in particular, I don't think you have a valid way to control the execution time for your functions from outside of them.Like you said, things like set_time_limit will throw a Fatar Error and kill your script.

I would suggest messuring your excecution time from within your functions, using things like microtime() and throw an exception if the time limit is exeeded; an exception that you'll be able to catch outside and continue act accordingly.