Transferring files

Franklin Bristow

Transfer files between your computer and a remote computer.

Doing your work on a remote computer using a command-line text editor like vim is fine, but it’s not exactly the most comfortable environment. Nothing is going to feel the same as working directly on your own computer.

Transferring files between your computer and a remote computer (to the remote computer and from the remote computer) is fairly straightforward. We’ll look at two different ways you can do it: using a graphical user interface (a GUI) and using command-line tools.

Using a GUI

You’re going to need to install a new program on your computer to get a GUI to transfer files between your computer and a remote computer. The program you use depends on the operating system that you’re using. The following are recommendations for software that you can use, but there are many different programs you can use to transfer files between computers.

You only need to install software (in Windows and macOS) if you are planning to use a GUI. You don’t need to install anything at all if you are planning on Using the command line to transfer files.

GUIs for Windows

MobaXterm is a full software suite for working with remote computers on Windows, including a(nother) terminal emulator.

If you’re planning on using MobaXterm, you should download the “Installer edition” — this has a .zip file that contains a .msi file, and you can install the .msi file in [the same way that you did with Pandoc].

After you’ve installed MobaXterm, launch it. You can then connect to a remote computer by clicking the “Start local terminal” button that’s right in the middle of the main window, then connecting the same way you did in your other terminal application, i.e.,

ssh you@name.remote.ca

Once you’re connected, MobaXterm will automatically display files and folders that you have on this remote system on the left side of the window.

You can transfer files from Aviary to your computer by right-clicking on the thing you want to copy to your computer and selecting “Download…”. You will then be asked where you want to put the files, and you can select the folder you want to put them into.

You can transfer files from your computer to Aviary by opening Windows Explorer, clicking on the file you want to copy to Aviary, and dragging it to the folder display on the left of MobaXterm. MobaXterm will then start transferring the file or folder that you’ve asked it to copy to the remote computer.

GUIs for macOS

Cyberduck is a tool designed specifically for transferring files between computers. Installing Cyberduck is the same process as installing VS Code (download the .zip file, copy the app into your Applications directory).

Once you’ve installed Cyberduck, create a new “SFTP” connection by clicking on the + button on the bottom left side of the window. In the list of options at the top, choose “SFTP (SSH File Transfer Protocol)”. The Server is the name and location (address) of the remote computer you want to connect to. Your username and password are the same ones you used to connect remotely with ssh. When you’ve finished entering that information, you can close this window, then double-click on the entry that was created in the main Cyberduck window.

Once you do that, you should see the files and folders that are on the remote computer 🎉! You can interact with this window the same way you do with your file explorer (e.g., drag files and folders to and from this window to transfer them).

GUIs for Linux

Depending on the distribution that you have installed, you may just be able to use your file explorer to connect to a remote computer with a GUI.

Open your file explorer program, and on the left side of the window look for an entry that says something like “Other locations”. You may see an option to “Connect to a server” at the bottom of the window.

Another alternative is that you may be able to enter an address directly into the address field.

If you see that option, you can enter the name and location of the remote computer you want to connect to, but you need to tell the file explorer software which “protocol” to use.

If you want to connect to aviary, you should enter ssh://aviary.cs.umanitoba.ca and enter your username and password when prompted.

If you’ve connected, then you’ll see the files and folders that you saw in your terminal in your regular file explorer window 🎉! You can interact with this window in the same way you do with other file explorer windows (e.g., drag files and folders to and from this window to transfer them).

Using the command line

Transferring files on the command line is the same regardless of which operating system you have on your computer.

Open your terminal, then navigate to the directory that contains the file or directory that you want to transfer from your computer to the remote computer.

Navigating directories on Windows, macOS, and Linux uses mostly the same commands: cd to change directories, cd .. to go back. The only notable difference that we care about right now is that Windows doesn’t have the ~ special directory.

When you’re navigating folders on your own computer (i.e., you’re not connected to something like Aviary with ssh), you can also take a shortcut to avoid typing out very long folder paths: Open your terminal, type cd (that’s cd with a single space after it), then open your visual file explorer. Find the folder that you want to navigate to, click the folder, then drag it to your terminal window and drop it. The path to that folder should show up in your terminal and then you can press Enter in your terminal to get there quickly.

Once you’ve navigated to that directory, we can use the scp program (secure copy) to transfer files from our computer to the remote computer.

When we’re copying files or folders with scp, we need to tell scp what we want to copy (the source) and where we want to copy it to (the destination).

Just like when using SSH, any time we want to use a remote computer as a source or a destination, we need to provide scp with our username and the address of the remote computer. But since we’re trying to send something, we also need to tell scp where we want to put the file (a destination on the remote computer).

Copying single files

scp source-file.md you@remote.name.ca:~/folder

source-file.md is the name of the file that you want to copy to the remote computer. Replace this with the name of the file that you want to copy.
you is where you put your username. Replace you with your username.
name.remote.ca is where you put the address of the remote computer. Replace name.remote.ca with the address that you want to send this file to.
:~/folder, the colon (:) separates the address from the destination on the remote computer, and the tilde (~/folder) is the name of the folder on the remote destination. Remember that ~ is a special name for a directory that is your user directory, and in this case folder would be the name of a folder in your user directory.

If you want to transfer the file directly to your user directory, you can completely leave out everything after the colon (:). For example, the command
```
scp source-file.md you@remote.name.ca:
```
copies the file into your user directory on the remote computer.

If I want to send a file named hello.md from my Desktop folder on my computer to aviary.cs.umanitoba.ca, then I would run:

cd Desktop
scp hello.md fbristow@aviary.cs.umanitoba.ca:

Similar to ssh, you will be prompted to enter your password, but you will get no feedback as you type in your password.

If you want to copy a file from a remote computer, you can also use scp, but you reverse the order: the file on the remote computer comes first (the source) and a place on our own computer comes second (the destination).

If I want to copy hello.md on Aviary back from the remote computer to my current directory (.), I might do something like:

scp fbristow@aviary.cs.umanitoba.ca:hello.md .

Copying directories

We’re not limited to copying individual files between computers. In fact, that would get really tedious if we had many files we wanted to copy, or entire folder structures!

Thankfully, we can copy entire directories using scp by passing an additional argument or flag to scp to tell it to copy things recursively.

To copy a directory either to or from a remote computer, we include -r after the scp command to tell it to copy recursively.

scp -r my-project you@remote.name.ca:

my-project is the name of a complete folder that you want to copy.
The destination part is the same as in copying a file.

Similarly, to copy from the remote computer we put the remote computer location first.

scp -r you@remote.name.ca:my-project .

The source part asks to copy the folder my-project that’s in your user directory.
The destination part is the same as in copying a file.