I have come across a Lenovo IdeaCentre A540-24ICB system with a scheduled task that wakes the computer to start my application and it seems to start but the system goes back to sleep right away. Sometimes it appears to not start (or goes to sleep so fast nothing is logged yet) so I checked the Windows power sleep options to ensure "Allow wake timers" was enabled but it didn't exist! Searching online I found a registry entry to add to have it show up in the power options and then ensured it's was enabled. However, didn't make a difference.
I have to use the mouse/keyboard for the computer to wake long enough to run the application (it will start where it left off). The application has been used for years and waking and running has worked. It already tells the system to not go to sleep through the api call in the main processing thread (which could take a fraction of a second to get to):
SetThreadExecutionState(ES_CONTINUOUS | ES_SYSTEM_REQUIRED);
I thought that API was enough to prevent system from going to sleep? As mentioned, it has worked for years. It's just this new Lenovo system or the Win10 installed with it doesn't seem to honor it? Is there some other API call that needs to be called? or any checks / fix the app should do to ensure the SetThreadExecutionState() will work?
TIA!!
Related
API Monitor has a feature to automatically watch for a new process starting and ask if you want to monitor it. However I have not been able to get this to actually work. The only option in the program I can find which seems to be related is the File menu "Pause Process Notifications" option. However, this is disabled which gives me the impressions that it can't be turned off but also that it is supposed to work automatically "out of the box". But whenever I start a new process, nothing happens.
Specifically I'm referring to the feature described here:
Process Notification
API Monitor intercepts process creation and allows you to select the
process for monitoring. Each time a process is created by the system,
a notification window is displayed with options to monitor, skip or
terminate the process. This is especially useful for monitoring
processes with a short lifespan or processes that are automatically
launched in the background. Process Notification can also be used to
monitor applications such as consent.exe (UAC prompt), which run on a
different desktop.
The following screenshot shows an example of the Process Notification
window that is displayed when launching an application that requires
elevation
I've tried both the 32-bit and 64-bit versions of API Monitor (Version 2.0 Alpha-r13) running both as regular user and as admin; makes no difference.
How can this feature be activated?
The specific reason I'd like to use this feature is that I have process A which starts process B, and it is B I need to monitor. A and B each run for only a few seconds so I can't manually get it to monitor fast enough.
Finally after reading through API Monitor forums I found some information. Unfortunately (for now at least) it seems the answer is that this feature no longer works (since Windows 8.1).
As posted on http://www.rohitab.com/discuss/topic/40418-process-notification-on-81/?p=10093378
rohitabPosted 11 October 2013 - 03:38 AM
Due to security related changes in Windows 8.1, the Process
Notifications feature of API Monitor does not work. I will try to
resolve this issue as soon as possible and post a hotfix.
But a later update in 2014 indicated that it hadn't been fixed yet, and seems not to have been since then either.
It was implied that running in a Windows 7 (or 8.0?) virtual machine might be a workaround, or obviously finding another tool which has this capability.
I have a computer-based test that takes several hours to complete.
However, the test is timed-out at some point, because my PC "goes to sleep in one way or another".
This is possibly related to the fact that the test consists of two processes which communicate with each other via port, so I'm suspecting that perhaps networking is disabled in some way (even if it's completely "local networking").
I have disabled both screen turn off and sleep in the Settings "page", under Power & Sleep.
Still no luck, the screen is locked with a password at some point, which I suspect causes the test to stop running in the background.
I even followed a procedure that I found on the web to disable screen-lock via Regedit in something like 18 steps (why on earth did this company figure out that this is a reasonable user experience).
Is there a solution to this problem?
Found a (very hacky) solution:
If you keep all windows minimized, then the screen doesn't get locked.
What a great operating system, by such a great company!!!
Yesterday I ran a BIOS update on a Windows7 computer. The BIOS update tool performed a shutdown of Windows and without restarting the computer (so directly after Windows shutdown), a DOS-like tool started that updated the BIOS.
I searched the WWW but all I can find is how to execute applications at Windows shutdown (so before windows goes down) or at logoff (logoff scripts).
Does anyone have any clue on how to achieve this?
It is my guess that the machine had in fact performed a soft-reboot and was running BIOS code. That's the usual approach, and in some cases the soft-reboot may not be visible to the user, i.e., the BIOS self-update code may run before the POST.
However, it is (or at least used to be) possible to run Windows code post-shutdown, although obviously it is limited in what it can do. The key information can be found in the MSDN library entry on the Service Control Handler Function:
After this time expires, system shutdown proceeds regardless of whether service shutdown is complete. Note that if the system is left in the shutdown state (not restarted or powered down), the service continues to run.
So, at least in principle, all you need to do is to install a service that asks for shutdown notification but does not actually stop when shutdown occurs, and then instruct Windows to shut down without rebooting or powering off. I have actually seen this happen, but only on older versions of Windows (before automatically powering off at shutdown became the default!) so I can't guarantee that it still works, although it definitely did once.
It should, however, be noted that this will not necessarily give you the sort of environment you may be thinking of. For example, device drivers are not necessarily unloaded before shutdown; after all, what would be the point?
You can run Local Group policy - gpedit.msc (From run).
Under Computer Configuration choose Windows Settings
choose Scripts(Startup/Shutdown)
On Shutdown properties you can add script and also mention parameters if needed.
I also advised you to look at the following question - how to delay shutdown and run a process in window service
When Mac OS X goes to sleep, due to closing a laptop or selecting "Sleep" from the Apple menu, how does it suspend an executing process?
I suppose non-windowed processes are simply suspended at an arbitrary point of execution. Is that also true for Cocoa apps, or does the OS wait until control returns to the run loop dispatcher, and goes to sleep in a "known" location? Does any modern OS do that, or is it usually safe enough to simply suspend an app no matter what it is doing?
I'm curious, because allowing sleep to occur at any moment means, from the app's perspective, the system clock could suddenly leap forward by a significant amount. That's a possibility I don't usually consider while coding.
Your app is interrupted exactly where it is that moment if the CPU is actually currently executing code of your app. Your app constantly gets execution time by the task scheduler, that decides which app gets CPU time, on which core, and for how long. Once the system really goes to sleep, the scheduler simply gives no time to your app any longer, thus it will stop execution wherever it is at that moment, which can happen pretty much everywhere. However, the kernel must be in a clean state. That means if you just made a call into the kernel (many libC functions do) and this call is not at some safe-point (e.g. sleeping, waiting for a condition to become true, etc.) or possibly holding critical kernel locks (e.g. funnels), the kernel may suspend sleep till this call returns back to user space or execution reaches such a safe-point before it finally cancels your app from the task scheduler.
You can open a kernel port and register for sleep/wake-up events. In that case, your app will receive an event, when the system wants to go to sleep. You have several possibilities. One is to reply to it, that the system may progress. Another one is to suspend sleep; however, Apple says certain events can be suspended at most 30 seconds, after that, the system will just continue, whether your app likes it or not. And finally, you can cancel it; though not all events can be canceled. If the system already decided it will go to sleep, you can only suspend this by at most 30 seconds or allow it at once, you cannot cancel it. However, you can also listen to an event, where the system asks apps, if it is okay to go to sleep now and there you can reply "no", causing a sleep to be canceled.
The difference between "Is it okay to sleep" and "I'm planing on going to sleep" is: The first one is sent if the power saving settings are applied, that is, if the user has not moved the mouse or typed anything for the time configured there. In that case the system will just ask, if sleep is okay. An app like Apple's DVD Player will say "no", because most likely the user watches a DVD and thus doesn't interact with the computer, still no reason to go to sleep. OTOH, if the user closes his Mac Book, apps are not asked, the system will go to sleep for sure and just informs apps, that have now up to 30 seconds to react to it.
Wake-up events can also be quite interesting to catch. E.g. if your system wakes up, open files might be inaccessible (an external drive has been unplugged) or network sockets won't work any longer (network has changed). So you may re-init certain app parts before using them and running into errors that are more or less expected.
Apple's page regarding catching these events.
It depends on your app.
If you are interacting with external systems (think networking or doing something over usb/firewire,etc) then it might be affected. An application running on OSX gets to run for a limited time ( max 10ms ) , after which it is interrupted by the kernel which schedules a new process from the process queue to run on the CPU. This is transparent for the application , which "thinks" that it runs all the time on the CPU. Thus , a transition to sleep is no different - apart from the time jumping ahead.
If you need to be aware that there was a transition to sleep mode please refer to this tech note which details how to receive notifications about the state change : Registering and unregistering for sleep and wake notifications
I believe it will just suspend all apps wherever they happen to be.
Remember, this happens all the time anyway. Applications are constantly suspended and resumed due to context switching. So, really, the clock could jump between any 2 instructions in your app, though usually not in a noticable/significant way.
If the OS waited for the app to return to some main loop you could run into situations where applications cause the sleep to hang. If they're doing a lot of work and not returning to the run loop dispatcher they would prevent the machine from going to sleep. That wouldn't be very good. :)
And if you set the time it also appears to leap forward to the running programs. Nothing special either.
Check out this Wikipedia article. Cavver is correct in stating that things like network connections may time out, and thus those services may be interrupted.
The product we are working on allows the user to easily set it up to run automatically whenever the computer is started. This is helpful because the product is part of the basic work environment of most of our users.
This feature was implemented not so long ago and for a while all was well, but when we started testing this feature on Vista the product started behaving really weird on startup. Specifically, our product makes use of another product (lets call it X) that it launches whenever it needs its services. The actual problem is that whenever X is launched immediately after log-on, it crashes or reports critical errors related to disk access (this happens even when X is launched directly - not through our product).
This happens whenever we run our product by registering it in the "Run" key in the registry or place a shortcut to it in the "Startup" folder inside the "Start Menu", even when we put a delay of ~20 seconds before actually starting to run. When we changed the delay to 70 seconds, all is well.
We tried to reproduce the problem by launching our product manually immediately after logon (by double-clicking on a shortcut placed on the desktop) but to no avail.
Now how is it possible that applications that run normally a minute after logon report such hard errors when starting immediately after logon?
This is the effect of a new feature in Vista called "Boxing":
Windows has several mechanisms that allow the user/admin to set up applications to automatically run when windows starts. This feature is mostly used for one of these purposes:
1. Programs that are part of the basic work environment of the user, such that the first action the user would usually take when starting the computer is to start them.
2. All sorts of background "agents" - skype, messenger, winamp etc.
When too many (or too heavy) programs are registered to run on startup the end result is that the user can't actually do anything for the first few seconds/minutes after login, which can be really annoying. In comes Vista's "Boxing" feature:
Briefly, Vista forces all programs invoked through the Run key to operate at low priority for the first 60 seconds after login. This affects both I/O priority (which is set to Very Low) and CPU priority. Very Low priority I/O requests do not pass through the file cache, but go directly to disk. Thus, they are much slower than regular I/O.
The length of the boxing period is set by the registry value:
"HKLM\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced\DelayedApps\Delay_Sec".
For a more detailed explanation see here and here
The program probably needs some more info put into its properties. It needs to "Run As", instead of just running.
Maybe this application should be developed as a service, instead of a program to be launched, or you could have service that launches the program when its determined the best window of opportunity.