fsockopen

Description

int fsockopen ( string target, int port [, int errno [, string errstr [, float timeout]]])

Initiates a socket connection to the resource specified by target. PHP supports targets in the Internet and Unix domains as described in Appendix J. A list of supported transports can also be retrieved using stream_get_transports().

As of PHP 4.3.0, if you have compiled in OpenSSL support, you may prefix the hostname with either 'ssl://' or 'tls://' to use an SSL or TLS client connection over TCP/IP to connect to the remote host.

fsockopen() returns a file pointer which may be used together with the other file functions (such as fgets(), fgetss(), fputs(), fclose(), and feof()).

If the call fails, it will return FALSE and if the optional errno and errstr arguments are present they will be set to indicate the actual system level error that occurred in the system-level connect() call. If the value returned in errno is 0 and the function returned FALSE, it is an indication that the error occurred before the connect() call. This is most likely due to a problem initializing the socket. Note that the errno and errstr arguments will always be passed by reference.

Depending on the environment, the Unix domain or the optional connect timeout may not be available.

The socket will by default be opened in blocking mode. You can switch it to non-blocking mode by using socket_set_blocking().

Example 1. fsockopen() Example <?php $fp = fsockopen ("www.example.com", 80, $errno, $errstr, 30); if (!$fp) { echo "$errstr ($errno)<br>\n"; } else { fputs ($fp, "GET / HTTP/1.0\r\nHost: www.example.com\r\n\r\n"); while (!feof($fp)) { echo fgets ($fp,128); } fclose ($fp); } ?>

The example below shows how to retrieve the day and time from the UDP service "daytime" (port 13) in your own machine.

Example 2. Using UDP connection <?php $fp = fsockopen("udp://127.0.0.1", 13, $errno, $errstr); if (!$fp) { echo "ERROR: $errno - $errstr<br>\n"; } else { fwrite($fp,"\n"); echo fread($fp, 26); fclose($fp); } ?>

See also pfsockopen(), socket_set_blocking(), socket_set_timeout(), fgets(), fgetss(), fputs(), fclose(), feof(), and the Curl extension.