9

This code always fails (i.e., $result is Boolean false):

     $ch = curl_init();
     curl_setopt($ch, CURLOPT_URL, $path);
     curl_setopt($ch, CURLOPT_HEADER, TRUE);
     curl_setopt($ch, CURLOPT_NOBODY, TRUE);
     curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
     $curl_version = curl_version();

     curl_setopt($ch, CURLOPT_CONNECTTIMEOUT_MS, 999);

     $result = curl_exec($ch);
     curl_close($ch);

This code always succeeds (i.e., $result is a string containing the header):

     $ch = curl_init();
     curl_setopt($ch, CURLOPT_URL, $path);
     curl_setopt($ch, CURLOPT_HEADER, TRUE);
     curl_setopt($ch, CURLOPT_NOBODY, TRUE);
     curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
     $curl_version = curl_version();

     curl_setopt($ch, CURLOPT_CONNECTTIMEOUT_MS, 1000);

     $result = curl_exec($ch);
     curl_close($ch);

The only difference is that I've changed the timeout from 999ms to 1000ms.

This must be either a bug in curl or some sort of minimum in the documentation for connection timeouts that I missed. Which is it? My money is on the latter.

Trott
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2 Answers2

13

from: http://www.php.net/manual/en/function.curl-setopt.php

The number of milliseconds to wait while trying to connect. Use 0 to wait indefinitely. If libcurl is built to use the standard system name resolver, that portion of the connect will still use full-second resolution for timeouts with a minimum timeout allowed of one second.

dev-null-dweller
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  • Ok, I saw this in the documentation but I really don't understand what it means and how I can make this to work with a smaller value than 1000. Any help you can give me would be appreciated, thanks! – Mihai Fratu Jan 10 '13 at 00:16
  • You have to compile libcurl for yourself, using `--enable-threaded-resolver` and then compile curl extension for php against it. – dev-null-dweller Jan 10 '13 at 00:40
4

Another way of dealing with this would be to set the CURLOPT_NOSIGNAL option to 1 in addition to the CURLOPT_CONNECTTIMEOUT_MS. See http://curl.haxx.se/libcurl/c/CURLOPT_NOSIGNAL.html for more info.

nonsenz
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