What does it mean to upload and download a file?

Simple sending or receiving files across the internet does not necessarily mean that you are already downloading or uploading files. Technically, the term download refers to receiving a file or a batch of files to their computer from a location, often a remote server. The term upload refers to the process of sending a file or a batch of files to a remote network location. These terms usually apply to client-server networking than in peer-to-peer networking.

There are a lot of ways that can be used to upload and/or download files, whether you use Windows-based systems or Unix-based systems. However, the process in how to upload or download may actually differ, depending upon the system that you used. The process that works for Windows-based system may not work with Unix-based systems.

How do I upload and download files in UNIX?

Unix-based system users can use any of the following processes to download or upload files. These are two of the commonly used processes:

  • SCP also known as Secure Copy protocol is a secure alternative to the traditional remote copy protocol (rcp) of sending and receiving files.
    o To upload:
    scp file…[email protected]:path ; where file is the file to be uploaded, user is your username on the remote system, host.domain is the address of the remote system and path is the absolute path name to the destination.
    o To download:
    Scp [email protected]:path…dest ; where user is your username on the remote system, host.domain is the address of the remote system; path is the absolute path name to the destination and dest is the path where you want the remote files to be copied.
  • FTP or file transfer protocol is considered as the most commonly used and easiest way to copy files to and from a remote system. Say for example, you want to download a file list.txt from sannic.com/Nicbirth/arch:
    o At the command prompt type:
    ftp ftp.sannic.com
    o On the screen, you will see something like:
    >Connected to smartsite.cnlab-switch.ch.
    >220 wcarchive.sannic.com FTP server (Version wu-2.4.2 (18) Tue
    >Dec105:05:46 MET 2013) ready
    >Name (carchive.sannic.com:user):
    o Type
    ftp
    o You will now see something like:>332 Guest login ok, send your complete e-mail address as password.
    >Password:
    o Type your e-mail address.
    o Once you are in the site, change the directory to the directory “Nicbirth/arch” by typing
    cd Nicbirth; where cd means Change Directory
    o Type “dir” to see the list of all the files. Look for ‘arch’ directory on the list and change it by typing “cd arch”
    o To find a file; type “dir l*”
    o To download, type “bin”, which makes your download in binary form, then type “get list.txt” then type “y” when asked to confirm.
    o “list.txt” should now start to download and will be in the computer where you run the ftp.
    o TO UPLOAD:
    o Make sure you are in the directory where you are allowed to upload into;
    o Using the same example, type “put list.txt” or simply type “mput l*” should you will to upload all files beginning with the letter L;
    o Again, make sure your type “bin” before you upload.
    o Then, simply type “bye” to log off FTP.

What are the usually used Unix FTP commands in uploading and downloading files?

  • Get “myfile” – used to download files
  • Put “myfile” – used to upload files
  • ls – list of files on server in current directory
  • ls-al –list of files in folder, with details
  • delete filename – delete file from server
  • rename filename – rename file in server
  • mkdir “dirname” – make directory called “dirname”

Why is downloading and uploading in Unix different from that of Windows?

The reason for the different processes involved is that the two systems has different file systems, which means that they have different ways of arranging their data and would often mean different programs to run those data properly. Simply, what works well with Unix based systems may not work with Windows and vice-versa.