Project 01: Process Queue Shell

This is Project 01 of CSE.30341.FA25.

Brainstorming

The following are questions that should help you in thinking about how to approach implementing Project 01.

Process

1. Given a command string such as sleep 10, how would you start a process that executes this command? In particular, how would you handle the name of the program (ie. sleep) versus the arguments to the program (ie. 10)?

2. What signals do you need to send to a process to pause it (ie. suspend its execution) or to resume it (ie. continue its execution)?

Queue

1. What must happen when pushing a process to a Queue?

2. What must happen when popping a process from a Queue?

3. What must happen when removing a process from a Queue?

Shell

1. What system call will allow us to trigger a timer event at periodic intervals? What signal does it send when a timer is triggered?

2. How will you interweave reading input from the user, handling periodic timers, and waiting for child processes?

3. What functions would allow you to parse strings with various arguments?

Scheduler

1. What needs to be created when calling scheduler_add and where should this object go?

2. How would you determine if you should display a particular queue in the scheduler_status function?

3. How would you wait for a process without blocking? What information do you need to update when a process terminates?

4. What should the scheduler handler functions do when they receive either a SIGALRM or a SIGCHLD?

5. When and where are scheduler_wait and scheduler_next called?

Timestamp

1. How would you use the result of clock_gettime to return a double representing the current time in seconds?

Errata

Describe any known errors, bugs, or deviations from the requirements. Response time may have issues but it works better than before.