Bad File Descriptor with FTP

[Anon]

While trying to upload a file to FTP, I get the following error:

Warning: fopen("ftp://...@.auxilium.vuurwerk.nl/cgi-bin/","w") - Bad file descriptor in /home/users65/hollax/www/php/lastinvoer.php on line 103

The lines read:
102: $connstring = "ftp://$ftp_user_name:$ftp_user_pass@$ftp_server/cgi-bin/";
103: $fp = fopen ($connstring, "w");
104: fwrite($fp, $fcontents, 26);
105: fclose($fp);

Please help..
(PS. Using FTP-commands is not an option.)

[[deleted]]

Did you read this section in the manual?

-- quote --

If filename begins with "ftp://" (not case sensitive), an ftp connection to the specified server is opened and a pointer to the requested file is returned. If the server does not support passive mode ftp, this will fail. You can open files for either reading or writing via ftp (but not both simultaneously).

-- end quote --

And why is using proper ftp not an option?