ftp_nb_get

(PHP 4 >= 4.3.0, PHP 5, PHP 7)

ftp_nb_get — Retrieves a file from the FTP server and writes it to a local file (non-blocking)

Description

ftp_nb_get ( resource $ftp_stream , string $local_file , string $remote_file [, int $mode = FTP_BINARY [, int $resumepos = 0 ]] ) : int

ftp_nb_get() retrieves a remote file from the FTP server, and saves it into a local file.

The difference between this function and ftp_get() is that this function retrieves the file asynchronously, so your program can perform other operations while the file is being downloaded.

Parameters

ftp_stream: The link identifier of the FTP connection.
local_file: The local file path (will be overwritten if the file already exists).
remote_file: The remote file path.
mode: The transfer mode. Must be either FTP_ASCII or FTP_BINARY.
resumepos: The position in the remote file to start downloading from.

Return Values

Returns FTP_FAILED or FTP_FINISHED or FTP_MOREDATA.

Changelog

Version	Description
7.3.0	The `mode` parameter is now optional. Formerly it has been mandatory.

Examples

Example #1 ftp_nb_get() example

<?php

// Initiate the download
$ret = ftp_nb_get($my_connection, "test", "README", FTP_BINARY);
while ($ret == FTP_MOREDATA) {
   
   // Do whatever you want
   echo ".";

   // Continue downloading...
   $ret = ftp_nb_continue($my_connection);
}
if ($ret != FTP_FINISHED) {
   echo "There was an error downloading the file...";
   exit(1);
}
?>

Example #2 Resuming a download with ftp_nb_get()

<?php

// Initiate 
$ret = ftp_nb_get($my_connection, "test", "README", FTP_BINARY, 
                      filesize("test"));
// OR: $ret = ftp_nb_get($my_connection, "test", "README", 
//                           FTP_BINARY, FTP_AUTORESUME);
while ($ret == FTP_MOREDATA) {
   
   // Do whatever you want
   echo ".";

   // Continue downloading...
   $ret = ftp_nb_continue($my_connection);
}
if ($ret != FTP_FINISHED) {
   echo "There was an error downloading the file...";
   exit(1);
}
?>

Example #3 Resuming a download at position 100 to a new file with ftp_nb_get()

<?php

// Disable Autoseek
ftp_set_option($my_connection, FTP_AUTOSEEK, false);

// Initiate
$ret = ftp_nb_get($my_connection, "newfile", "README", FTP_BINARY, 100);
while ($ret == FTP_MOREDATA) {

   /* ... */
   
   // Continue downloading...
   $ret = ftp_nb_continue($my_connection);
}
?>

In the example above, newfile is 100 bytes smaller than README on the FTP server because we started reading at offset 100. If we didn't disable FTP_AUTOSEEK, the first 100 bytes of newfile would be '\0'.