Part 4. Making a shell (15 points)
Congratulations, you’ve completed the difficult part! All that remains is to turn your code into a proper shell.
Here’s a short sample session with my implementation.
Welcome to the Oberlin Shell!
$ whoami
steve
$ date
Wed Oct 18 13:51:00 EDT 2023
$ echo "I can run" 'commands with' multiple' 'arguments | tr a-z A-Z
I CAN RUN COMMANDS WITH MULTIPLE ARGUMENTS
$ ^D
To exit the shell, I pressed Ctrl-D (which it printed as ^D
). This causes stdin to be closed.
Your task
Modify your main()
function to print out a welcome message and then read
lines of input in a loop, parse their input, build a pipeline, and run the
pipeline. Any error should be printed out but the shell should not exit.
If the user enters a line containing only whitespace, the line should be ignored and the prompt printed again.
I found it helpful to separate out the logic of reading a line, parsing it,
and running it into a separate function which returned a Result<()>
and then
in main()
, I have a loop that calls the function and if it returns an error,
print the error out.