ftp_nb_fput() function in PHP

The ftp_nb_fput() function uploads data from an open file pointer to a file on the FTP server using non-blocking mode. This allows your script to continue processing while the upload happens in the background.

Syntax

ftp_nb_fput(con, remote_file, open_file, transfer_mode, beg_pos);

Parameters

• con − The FTP connection resource

• remote_file − The remote file path on the FTP server

• open_file − The file pointer resource opened with fopen()

• transfer_mode − The transfer mode. Possible values:

  − FTP_ASCII for text files

  − FTP_BINARY for binary files

• beg_pos − (Optional) The position to start uploading from

Return Value

The function returns one of the following constants ?

• FTP_FAILED − Upload failed

• FTP_FINISHED − Upload completed successfully

• FTP_MOREDATA − Upload still in progress

Example

Here's how to upload a file using non-blocking mode ?

<?php
    $ftp_server = "192.168.0.4";
    $ftp_user = "jacob";
    $ftp_pass = "tywg61gh";
    
    // Establish connection
    $con = ftp_connect($ftp_server) or die("Could not connect to $ftp_server");
    $login = ftp_login($con, $ftp_user, $ftp_pass);
    
    $my_serverfile = "demo.txt";
    $local_file = "new.txt";
    
    // Open local file for reading
    $file_pointer = fopen($local_file, "r");
    
    // Start non-blocking upload
    $result = ftp_nb_fput($con, $my_serverfile, $file_pointer, FTP_BINARY);
    
    // Continue until upload is complete
    while ($result == FTP_MOREDATA) {
        // Continue uploading
        $result = ftp_nb_continue($con);
        echo "Upload in progress...<br>";
    }
    
    // Check final result
    if ($result != FTP_FINISHED) {
        echo "Error uploading the file!";
        exit(1);
    } else {
        echo "File uploaded successfully!";
    }
    
    // Clean up
    fclose($file_pointer);
    ftp_close($con);
?>

Key Points

• Use ftp_nb_continue() to check upload progress

• Always close the file pointer with fclose()

• Use FTP_BINARY for most file types to preserve data integrity

• The function is non-blocking, allowing other operations during upload

Conclusion

The ftp_nb_fput() function provides efficient non-blocking file uploads to FTP servers. Use it when you need to upload files while keeping your script responsive for other tasks.