An instructional operating system based on Harvard's OS/161 with our own custom from-scratch implementations of:

• Synchronization (locks, condition variables, reader-writer locks)
• File system call interface (open, close, read, write, getpid, dup2)
• User process support (fork, execv, sbrk)
• Fully-featured virtual memory subsystem with TLB management and LRU swapping.

For setup, see: https://ops-class.org/asst/setup/

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Passes all test161 test suites with a perfect score. Unfortunately the leaderboards are no longer online.

For testing, see: https://github.com/ops-class/test161

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For more information about Harvard's OS/161: http://os161.org/