SWC-like Workshop: Introduction to the Unix Shell

King's College London

Online

November 16, 18, and 19, 2021 (optional session: November 26)

2:00 pm - 5:00 pm

Instructors: Stefania Marcotti, Flavia Flaviani, Alessia Visconti

Helpers: Kai Xiang Lim, Fursham Hamid, James Cain

General Information

Software Carpentry aims to help researchers get their work done in less time and with less pain by teaching them basic research computing skills. This hands-on workshop will cover basic concepts and tools, including program design, data management, and task automation. Participants will be encouraged to help one another and to apply what they have learned to their own research problems.

For more information on what we teach and why, please see our paper "Best Practices for Scientific Computing".

Who: The course is aimed at graduate students and other researchers. You don't need to have any previous knowledge of the tools that will be presented at the workshop.

Where: This training will take place online. The instructors will provide you with the information you will need to connect to this meeting.

When: November 16, 18, and 19, 2021 (optional session: November 26). The optional session will be held 2-3:15pm.

Requirements: Participants must have access to a computer with a Mac, Linux, or Windows operating system (not a tablet, Chromebook, etc.) that they have administrative privileges on. They should have a few specific software packages installed (listed below).

Accessibility: We are dedicated to providing a positive and accessible learning environment for all. Please notify the instructors in advance of the workshop if you require any accommodations or if there is anything we can do to make this workshop more accessible to you.

Contact: Please email carpentries@kcl.ac.uk for more information.

Roles: To learn more about the roles at the workshop (who will be doing what), refer to our Workshop FAQ.

Who can attend?: This workshop is open to affiliates to King's College London. If you are interested in attending this workshop, contact carpentries@kcl.ac.uk for more information.


Code of Conduct

Everyone who participates in Carpentries activities is required to conform to the Code of Conduct. This document also outlines how to report an incident if needed.


Collaborative Notes

We will use these collaborative documents for chatting, taking notes, and sharing URLs and bits of code.


Surveys

Please be sure to complete these surveys before and after the workshop.

Pre-workshop Survey

Post-workshop Survey


Schedule

Day 1

Before starting Pre-workshop survey
14:00 Intro
14:30 Why the Unix shell?
14:45 Navigating files and directories
15:30 Break
15:45 Working with files and directories
16:45 Feedback and closing remarks

Day 2

14:00 Recap of day 1
14:15 Pipes and filters (part 1)
15:00 Break
15:15 Pipes and filters (part 2)
16:00 Finding things
16:45 Feedback and closing remarks

Day 3

14:00 Recap of day 2
14:15 Loops (part 1)
15:00 Break
15:15 Loops (part 2)
15:45 Shell scripting
16:45 Feedback and closing remarks
End Post-workshop survey

Day 4 (optional)

14:00 Additional exercises
15:00 Feedback and closing remarks

Setup

To participate in a Software Carpentry workshop, you will need access to software as described below. In addition, you will need an up-to-date web browser.

We maintain a list of common issues that occur during installation as a reference for instructors that may be useful on the Configuration Problems and Solutions wiki page.

Install the videoconferencing client

If you haven't used Zoom before, go to the official website to download and install the Zoom client for your computer.

Set up your workspace

Like other Carpentries workshops, you will be learning by "coding along" with the Instructors. To do this, you will need to have both the window for the tool you will be learning about (a terminal, RStudio, your web browser, etc..) and the window for the Zoom video conference client open. In order to see both at once, we recommend using one of the following set up options:

This blog post includes detailed information on how to set up your screen to follow along during the workshop.

The Bash Shell

Bash is a commonly-used shell that gives you the power to do tasks more quickly.

  1. Download the Git for Windows installer.
  2. Run the installer and follow the steps below:
    1. Click on "Next" four times (two times if you've previously installed Git). You don't need to change anything in the Information, location, components, and start menu screens.
    2. From the dropdown menu select "Use the Nano editor by default" (NOTE: you will need to scroll up to find it) and click on "Next".
    3. On the page that says "Adjusting the name of the initial branch in new repositories", ensure that "Let Git decide" is selected. This will ensure the highest level of compatibility for our lessons.
    4. Ensure that "Git from the command line and also from 3rd-party software" is selected and click on "Next". (If you don't do this Git Bash will not work properly, requiring you to remove the Git Bash installation, re-run the installer and to select the "Git from the command line and also from 3rd-party software" option.)
    5. Ensure that "Use the native Windows Secure Channel Library" is selected and click on "Next".
    6. Ensure that "Checkout Windows-style, commit Unix-style line endings" is selected and click on "Next".
    7. Ensure that "Use Windows' default console window" is selected and click on "Next".
    8. Ensure that "Default (fast-forward or merge) is selected and click "Next"
    9. Ensure that "Git Credential Manager Core" is selected and click on "Next".
    10. Ensure that "Enable file system caching" is selected and click on "Next".
    11. Click on "Install".
    12. Click on "Finish" or "Next".
  3. If your "HOME" environment variable is not set (or you don't know what this is):
    1. Open command prompt (Open Start Menu then type cmd and press Enter)
    2. Type the following line into the command prompt window exactly as shown:

      setx HOME "%USERPROFILE%"

    3. Press Enter, you should see SUCCESS: Specified value was saved.
    4. Quit command prompt by typing exit then pressing Enter

This will provide you with both Git and Bash in the Git Bash program.

Video Tutorial

The default shell in some versions of macOS is Bash, and Bash is available in all versions, so no need to install anything. You access Bash from the Terminal (found in /Applications/Utilities). See the Git installation video tutorial for an example on how to open the Terminal. You may want to keep Terminal in your dock for this workshop.

To see if your default shell is Bash type echo $SHELL in Terminal and press the Return key. If the message printed does not end with '/bash' then your default is something else and you can run Bash by typing bash

If you want to change your default shell, see this Apple Support article and follow the instructions on "How to change your default shell".

Video Tutorial

The default shell is usually Bash and there is usually no need to install anything.

To see if your default shell is Bash type echo $SHELL in a terminal and press the Enter key. If the message printed does not end with '/bash' then your default is something else and you can run Bash by typing bash.

Text Editor

When you're writing code, it's nice to have a text editor that is optimized for writing code, with features like automatic color-coding of key words. The default text editor on macOS and Linux is usually set to Vim, which is not famous for being intuitive. If you accidentally find yourself stuck in it, hit the Esc key, followed by :+Q+! (colon, lower-case 'q', exclamation mark), then hitting Return to return to the shell.

nano is a basic editor and the default that instructors use in the workshop. It is installed along with Git.

nano is a basic editor and the default that instructors use in the workshop. See the Git installation video tutorial for an example on how to open nano. It should be pre-installed.

Video Tutorial

nano is a basic editor and the default that instructors use in the workshop. It should be pre-installed.