CS:APP Shell, my attempt at a practice assignment from "Computer Systems: A Programmer's Perspective" to implement a rudimentary Unix shell, which can fork child processes to run commands, intercept Ctrl+C and Ctrl+Z signals to forward to child processes, run processes in the background by appending a & to the command, and list and kill jobs. Aside from some clunkiness I hope to come back and amend regarding the interaction between the user input prompt and printed information from incoming signals, I think I dare say for a textbook assignment my implementation is Decent, given that the book and assignment didn't quite aim to produce a real-world robust shell so much as a seed for what one might look like. (I also went out of my way to figure out Unix methods for getting the username and hostname for the prompt!)

I also used the assignment as an excuse to play with some features of the C23 standard, e.g. attributes and nullptr.

Log from a simple example session:

./csh

joculatrix@shagohod> ./scripts/sleep.sh 50 &
[0] 23285
joculatrix@shagohod> ./scripts/sleep.sh 50 &
[1] 23287
joculatrix@shagohod> jobs

 JOB   PID   STATUS COMMAND
   0 23285  Running ./scripts/sleep.sh 50 &
   1 23287  Running ./scripts/sleep.sh 50 &

joculatrix@shagohod> kill %1
joculatrix@shagohod>
[1] killed  ./scripts/sleep.sh 50 &
joculatrix@shagohod> kill 23285
joculatrix@shagohod>
[0] killed  ./scripts/sleep.sh 50 &
joculatrix@shagohod> jobs

 JOB   PID   STATUS COMMAND

joculatrix@shagohod> quit