CS170 The KOS Pipes Lab Rubric

• 10 points: Building
  • 10 points: Makefile allows successful build
• 100 points: General Implementation
  • 90 points: Correct fd implementation (e.g. per process fd table and a system-wide open file/device table)
  • 10 points: fd table size is consistent with other syscalls
• 50 points: dup
  • 10 points: Correct return - new fd is lowest available fd
  • 10 points: Checks for major error conditions
  • 30 points: Correct internal fd handling (ref counting, device type, etc)
• 60 points: dup2
  • 10 points: Checks for major error conditions
  • 10 points: Do nothing when old fd equals new fd
  • 15 points: Correct internal fd handling (ref counting, device type, etc)
  • 15 points: Correct return - new fd
  • 10 points: Correct close behavior if target fd was open
• 150 points: pipe
  • 75 points: Correct pipe implementation (changes to fd table, internal entries/ref counts, etc)
  • 25 points: Correct arg (fildes[2]) on success and no changes to arg (fildes[2]) on failure
  • 50 points: Checks for major error conditions
• 150 points: read
  • 50 points: General pipe read works (buffering, multiple readers, etc)
  • 25 points: Console read( still works)
  • 50 points: Pipe block and unblock behavior
  • 10 points: Pipe blocks if pipe is open (writers exist) and there is nothing read
  • 20 points: Pipe unblocks if pipe is open (writers exist) and something was read (but not the full requested read)
  • 20 points: Pipe unblocks if write end is closed (no writers)
  • 25 points: Checks for major error conditions
• 150 points: write
  • 50 points: General pipe write works (buffering, multiple writers, etc)
  • 25 points: Console write (still works)
  • 50 points: Pipe block and unblock behavior
  • 20 points: Pipe blocks if pipe is open (readers exist) and pipe is full
  • 30 points: Pipe unblocks if read end is closed (no readers)
  • 25 points: Checks for major error conditions
• 40 points: fork
  • Correct fd table handling (ref counts, etc)
• 30 points: exec
  • Correct fd table handling (preserve fd table)
• 30 points: close
  • Decrements reference counts, frees pipes as needed (excluding read/write unblock behavior as it's part of read/write syscall)
• 30 points: exit
  • Closes the process's open file descriptors, etc