Software Engineering Stack Exchange
Software Engineering Stack Exchange

Questions tagged [signals]

12 questions
23
votes
5 answers

Where did usage of OS signals go?

From what books I read on linux system programming, it seems like signals were the primary way to communicate events between processes. They were the gateway into many interesting functionalities, like timers, interrupting sleeping threads, IO…
Incomputable
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13
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2 answers

Proper way of handling EINTR in libraries

What is the recommended etiquette when it comes to EINTR in libraries? I'm currently writing a function that does some file system tasks with the POSIX API, but a lot of the calls I use can potentially return EINTR. Additionally, the function can…
Rufflewind
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11
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1 answer

Why would it take hours to decode transmissions from Curiosity rover via MRO?

This video clip by NASA says that data from Curiosity relayed by the Mars Reconnaissance Orbiter (MRO) would be stored for a few hours, then transmitted to Earth (apparently taking about 14 minutes), after which it would take hours for engineers to…
Matt
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6
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3 answers

Real-time Dataflow Programming

Background Recently, I have been fascinated about the possibilities of dataflow-based programming approaches - in particular, signal/event-based concepts as realized by functional reactive programming, Boost::Dataflow::Signals, and the like. Sample…
Frank
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3
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2 answers

Prevent anomalies caused by signal propagation time

In electrical engineering class we learned that signal lines are not ideal, so it takes time for the signal to reach the other end of the cable, and if we doesn't take this into account, it can lead to crazy phenomenons like: Imagine we have a tank…
totymedli
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1 answer

Difference between Signal/Slot and DataBusPattern

I'm just trying to figure out what makes the Signal/Slot (Pattern?). Wikipedia tells me not so much and calls it an implementation of the ObserverPattern* while I would think it has much more resemblance to the DataBusPattern**. Can someone explain…
Scheintod
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1 answer

Connect private methods to Signals

I've recently been working on a customerproject that makes extensive use of a signals/slots like mechanism. Their approach is to directly connect signals from a larger framework to private methods of their businessobjects. Now, my role has mostly to…
rincewound
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How can I emulate Signals and Slots found in Qt, to Javascript / Typescript Classes?

Ive brought this up with other developers, and they say while there is no obvious way forward, it seems that they all have an idea of how to go about it. Is there any way I can implement signals and slots javascript and or typescript? I want to get…
Anon
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1 answer

Best way to signal all child processes to terminate using C

I have been assigned the task of designing a simple web server using C in my UNIX & C class. The webserver listens and forks when a successful connection is made so that multiple clients may be served at once. The child process then handles the…
sulay
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1 answer

Operating systems theory -- using minimum number of semaphores

This situation is prone to deadlock of processes in an operating system and I'd like to solve it with the minimum of semaphores. Basically there are three cooperating processes that all read data from the same input device. Each process, when it…
stackuser
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0
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1 answer

Weighted correlation coefficient

My problem is to classify input time series signal (128 points, equidistant in time, range 0.0..1.0) in limited amount (say 16) different classes. We have hand-classified 20000 samples and we are using 2000 as training set and other 18000 to…
SavinG
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1 answer

Good practice using signals and event driven system

I am using signals (specifically Boost signals2) to create an event driven protocol API and model. Most elements have their own signals, and there are usually multiple of each element. Consider a basic entity, a user; amongst others, the user may…
111111
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