Are there constants for PHP socket error codes?

[Chansen]

I'm connecting to a remote host as follows:\[code\]$conn = stream_socket_client("ssl://$host:$port", $e_code, $e_string, 2, STREAM_CLIENT_CONNECT, $ctx);\[/code\]How should I interpret the error code?The docs say the error code "holds the system level error number that occurred in the system-level connect() call."I can't find any PHP constants which define these error codes.