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Upload lecture slides, PDFs or a recording. Jay writes the summary, flashcards and a practice quiz, and cites the page behind every answer.
Lecture 7: Monitors and semaphores
A monitor bundles shared state with the synchronisation that protects it, so only one thread can act inside at a time. A semaphore is the lower-level tool: a counter with wait and signal.
Key points
- 1Race conditions occur when the result depends on thread timing.p. 6
- 2A mutex has an owner; a binary semaphore does not.p. 13
- 3Deadlock needs all four Coffman conditions. Break one to prevent it.p. 20
Key terms
- Critical section
- Mutex
- Semaphore
- Monitor
- Deadlock
Question 3 of 10Which condition is NOT required for deadlock?
Right. Deadlock needs no pre-emption: if resources can be taken away, the cycle breaks. See p. 27.
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From the first lecture to your first internship, CampusAI keeps up with where you are.
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Each new lecture becomes a summary, a set of flashcards and a short quiz. Your progress is tracked by course.
See Ask JayExam season
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Past papers from your school, with worked answers and timed mock exams to practise under pressure.
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Jay answers from your materials and shows the page it used. It does not write assignments.
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Is the Free plan really free?
Yes. It has no time limit and needs no payment details. Scholar removes the limits and adds exam tools when you want them.
Is Jay allowed by my school’s academic policy?
Jay explains your own course materials and cites them. It does not write assignments, and your uploads are never shared.
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Yes. MTN MoMo, Telecel Cash and AirtelTigo Money are supported, as well as Visa and Mastercard.
iPhone and Android
The app is on its way.
Study offline on the trotro, get a reminder before each lecture, and pick up on your phone where you left off on the web.
Coming to the App Store and Google Play in 2027.
