Ever needed to create an FTP connection resource defaulted to a particular dir from a URI? Here's a simple function that will take a URI like ftp://username:password@subdomain.example.com/path1/path2/, and return an FTP connection resource.
<?php
function getFtpConnection($uri)
{
// Split FTP URI into:
// $match[0] = ftp://username:password@sld.domain.tld/path1/path2/
// $match[1] = ftp://
// $match[2] = username
// $match[3] = password
// $match[4] = sld.domain.tld
// $match[5] = /path1/path2/
preg_match("/ftp:\/\/(.*?):(.*?)@(.*?)(\/.*)/i", $uri, $match);
// Set up a connection
$conn = ftp_connect($match[1] . $match[4] . $match[5]);
// Login
if (ftp_login($conn, $match[2], $match[3]))
{
// Change the dir
ftp_chdir($conn, $match[5]);
// Return the resource
return $conn;
}
// Or retun null
return null;
}
?>
ftp_connect
(PHP 4, PHP 5)
ftp_connect — Opens an FTP connection
Description
$host
[, int $port = 21
[, int $timeout = 90
]] )
ftp_connect() opens an FTP connection to the
specified host.
Parameters
-
host -
The FTP server address. This parameter shouldn't have any trailing slashes and shouldn't be prefixed with ftp://.
-
port -
This parameter specifies an alternate port to connect to. If it is omitted or set to zero, then the default FTP port, 21, will be used.
-
timeout -
This parameter specifies the timeout for all subsequent network operations. If omitted, the default value is 90 seconds. The timeout can be changed and queried at any time with ftp_set_option() and ftp_get_option().
Return Values
Returns a FTP stream on success or FALSE on error.
Examples
Example #1 ftp_connect() example
<?php
$ftp_server = "ftp.example.com";
// set up a connection or die
$conn_id = ftp_connect($ftp_server) or die("Couldn't connect to $ftp_server");
?>
Changelog
| Version | Description |
|---|---|
| 4.2.0 |
timeout was added.
|
See Also
- ftp_close() - Closes an FTP connection
- ftp_ssl_connect() - Opens an Secure SSL-FTP connection
Connecting through a firewall also depends on the type. This is an example for the Secure Gateway FTP. First you have to connect to the firewall, then open a session to the destination ftp server. This looks like this:
// Connect to firewall
$conn_id = ftp_connect("firewall.yournet.com");
// Open a session to an external ftp site
$login_result = ftp_login ($conn_id, "userid@externalhost.com", "password");
// Check open
if ((!$conn_id) || (!$login_result)) {
echo "Ftp-connect failed!"; die;
} else {
echo "Connected.";
}
// turn on passive mode transfers
ftp_pasv ($conn_id, true) ;
... and go on ...
always keep an eye on the ftp_pasv function, if you are behind a firewall or nat'ed and your scripts won't do a listing or put files to the ftp
Although an FTP port is always a number, if you specify it as one like this:
<?php $ftp = ftp_connect('example.com',210); ?>
You'll get a non-intuitive error. This, however, works [note the quotes]:
<?php $ftp = ftp_connect('example.com','210'); ?>
In testing, I have been unable to establish any socket connections (including FTP connections) on shutdown. This is important if you are trying to save the FTP transfer to run after the php script has been executed (using register_shutdown_function). I am unaware of any configuration options that control this, and I have found this affects any socket connections I have tried to establish after shutdown.
The same code works fine if it is executed at runtime, rather than on shutdown. Since I found no documentation of this behavior, I felt it important to note somewhere. May also be useful if this was crosslinked to fsockopen comments as well.
