Get non-blocking stdin data in Dart - asynchronous

Would really like to retrieve the entire line as it is typed before it is submitted so checks can be run before the user adds a line break? How would one accomplish this?
Thank you for reading.

You can archive this by setting stdin.lineMode to false. In that case you get a stream event for every character typed instead of only one per line. If you want to handle the outputing of the entered character on your own, you can also disable stdin.echoMode. In that case you have to pring the entered characters on your own. You have to enable it again after your program exits, otherwise the terminal stays in that mode.
One problem is that you are unable to reactivate echoMode in case of a program crash as there is no global crash handler. See issue 17743 for that.

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Vulkan: trouble understanding cycling of framebuffers

In Vulkan,
A semaphore(A) and a fence(X) can be passed to vkAcquireNextImageKHR. That semaphore(A) is subsequently passed to vkQueueSubmit, to wait until the image is released by the Presentation Engine (PE). A fence(Y) can also be passed to vkQueueSubmit. Client code can check when the submission has completed by checking fence(Y).
When fence(Y) signals, this means the PE can display the image.
My question:
How do I know when the PE has finished using the image after a call to vkQueuePresentKHR? To me, it doesn't seem that it would be by checking fence(X), because that is for client code to know when the image can be written to by vkQueueSubmit, isn't it? After the image is sent to vkQueueSubmit, it seems the usefulness of fence(X) is done. Or, can the same fence(X) be used to query the image availability after the call to vkQueuePresentKHR?
I don't know when the image is available again after a call to vkQueuePresentKHR, without having to call vkAcquireNextImageKHR.
The reason this is causing trouble for me is that in an asynchronous, 60fps, triple buffered app (throwaway learning code), things get out of wack like this:
Send an initial framebuffer to the PE. This framebuffer is now unavailable for 16 milliseconds.
Within the 16ms, acquire a second image/framebuffer, submit commands, but don't present.
Do the same as #2, for a third image. We submit it before 16ms.
16ms have gone by, so we vkQueuePresentKHR the second image.
Now, if I call vkAcquireNextImageKHR, the whole thing can fail if image #1 is not yet done being used, because I have acquired three images at this point.
How to know if image #1 is available again without calling vkAcquireNextImageKHR?
How do I know when the PE has finished using the image after a call to vkQueuePresentKHR?
You usually do not need to know.
Either you need to acquire a new VkImage, or you don't. Whether PE has finished or not does not even enter that decision.
Only reason wanting to know is if you want to measure presentation times. There's a special extension for that: VK_GOOGLE_display_timing.
After the image is sent to vkQueueSubmit, it seems the usefulness of fence(X) is done.
Well, you can reuse the fence. But the Implementation has stopped using it as soon as it was signaled and won't be changing its state anymore to anything, if that's what you are asking (and so you are free to vkDestroy it or do other things with it).
I don't know when the image is available again after a call to vkQueuePresentKHR, without having to call vkAcquireNextImageKHR.
Hopefully I cover it below, but I am not precisely sure what the problem here is. I don't know how to eat a soup without a spoon neither. Simply use a spoon— I mean vkAcquireNextImageKHR.
Now, if I call vkAcquireNextImageKHR, the whole thing can fail if image #1 >is not yet done being used, because I have acquired 3 images at this point.
How to know if image #1 is available again without calling >vkAcquireNextImageKHR?
How is it any different than image #1 and #2?
Yes, you may have already acquired all the images the swapchain has to offer, or the PE is "not ready" to give away an image even if it has two.
In the first case the spec advises against calling vkAcquireNextImageKHR with timeout of UINT64_MAX. It is a simple matter of counting the successful vkAcquireNextImageKHR calls vs the vkQueuePresentKHRs. One way may be to simply do one vkAcquireNextImageKHR and then do one vkQueuePresentKHR.
In the second case you can simply call vkAcquireNextImageKHR and you will eventually get the image.
In order to use a swapchain image, You need to acquire it. After that the actual availability of the image for rendering purposes is signaled by the semaphore (A) or the fence (X). You can either use the semaphore (X) during the submission as a wait semaphore or wait on the CPU for the fence (X) and submit after that. For performance reasons the semaphore is a preferred way.
Now when You present an image, You give it back to the Presentation Engine. From now on You cannot use that image for whatever purposes. There is no way to check when that image is available again for You so You can render into it again. You cannot do that. If You want to render into a swapchain image again, You need to acquire another image. And during this operation You once again provide a semaphore or a fence (probably different than those provided when You previously acquired a swapchain image). There is no other way to check when an image is again available than through calling the vkAcquireNextImageKHR() function.
And when You want to implement triple-buffering, You should just select appropriate presentation mode (mailbox mode is the closest match). You shouldn't wait for a specific time before You present an image. You just should present it when You are done rendering into it. Your synchronization should be entirely based on acquire, present commands and semaphores or fences provided during these operations and during submission. Appropriate present mode should do the rest. Detailed explanation of different present modes is available in Intel's tutorial.

Is there a AutoIt keypress example?

I am reading AutoIt Your Quick Guide but still not sure how to actually implemented it.
My setting, a opened notpad waiting for input.
What I want to do is to have a while loop and continue press a keystroke (e.g. keycode 20, #3 key, or multiple keystrokes) in a random period to that opened notepad.
How do I do it? I know send a keypress is using function Send ( "keys" [, flag = 0] ) But there is no number key reference in the book, and how do I tell the autoit to send keystroke to the specific program (notepad, in my example)
How I connect these all together?
Thanks for your help.
Look at ControlSend() in the help file, there is a Notepad example for you to decipher. Send() is a little unpredictable when you wish to send keystrokes to a particular window, as AutoIt simulates the keystrokes and thus if another window takes focus during the loop, then this will receive the keys.

Call an IDL routine from command line in Windows and prevent (or ignore) popup dialog boxes

I've written a short script (in another language, happens to be Python) which passes arguments to the command line as follows -
ildrt <path/filename.sav> -args p1 p2 --o1 --o2
where p, o are positional and optional arguments respectively (obvious). To get to the point, this script calls an IDL routine any number of times. Each time, the IDL virtual machine is loaded, the IDL routine runs until completion, rinse and repeat.
Unfortunately if an error occurs in the IDL routine execution a dialog box will popup and halt program execution until manually clicked. Since the idea is to run this as a batch process I want to ignore the dialog boxes, (accepting the error), and continue to the next run. Any thoughts on preferences or optional commands I can run IDL with to prevent the popups? Thanks in advance.
I guess I'm not following. Can't you just pass a flag to your program and then check that flag before popping up a dialog in your code? If you don't have access to the .pro code, then I don't think you can prevent the popups.

AT command for disable Radio Signal Strength Indication and alike?

Im working on a program to send and recieve SMS using a GSM modem and my computer.
I have gotten sending and receiving to work - well sort of.
Once in a while my program is sent into a total chrash due to modem is mixing up information about Radio Signal Strength Indication and alike, while also serving my program with the hex code for the message.
My code can handle the hex code just fine. but I have seen the following line popup while im decoding a byte stream:
^RSSI: 2
So far I've seen it send out values between 1 and 10.
Is there an AT Command that can disable them? I have no need for them.
Or alternative: Is there a general syntax for them, so I can filter them out before decoding?
Im leaning towards a filter solution. But that would be more easy to implement if I knew whenever modem is sending out on the form: "^SOMETHING: xxx", then It would be nice to know if it is always followed up be a delimiter say for instance "\r".
You should try turning off periodic messages as using AT^CURC=0.
Information regarding the AT^CURC command:
AT^CURC? Current setting of periodic status messages
AT^CURC=? See what you possible values are
AT^CURC=0 turn off periodic status messages
The best way to tackle this scenario would be to replace that part of the response with an empty string because otherwise, it will be difficult to check even if the command sent to disable it is working or not.
This regex will match all those. You can replace them ideally by an empty string.
(\\n|\\r|\\r\\n)\\^.*(\\n|\\r|\\r\\n)

AutoIt: Run next command after finishing the previous one

I'm currently writing a macro that performs a series of control sends and control clicks.
They must be done in the exact order.
At first I didn't have any sleep statements, so the script would just go through each command regardless whether the previous has finished or not (ie: click SUBMIT before finish sending the input string)
So I thought maybe I'll just put some sleep statements, but then I have to figure out how best to optimize it, AND I have to consider whether others' computers' speeds because a slow computer would need to have longer delays between commands. That would be impossible to optimize for everyone.
I was hoping there was a way to force each line to be run only after the previous has finished?
EDIT: To be more specific, I want the controlsend command to finish executing before I click the buttons.
Instead of ControlSend, use ControlSetText. This is immediate (like GuiEdit).
My solution: use functions from the user-defined library "GuiEdit" to directly set the value of the textbox. It appears to be immediate, thus allowing me to avoid having to wait for the keystrokes to be sent.

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