Programmatically, how do I:
a) Find all the processess running on my Blackberry?
b) Which of those processes are running in the background?
Is there an api or documentation I can look at, or maybe get a coded example?
Thanks in advance for any help
Take a look at this answer, making sure to note the comment below the actual answer. You need to request all the module handles on the device, and then for each, check to see if they're running.
Also, see this BlackBerry forum response, with the content quoted here, because it's a non-SO site:
Get all module handles (perhaps w/o siblings)
Traverse through the handle list and filter out library types (leaves us CLDC/Midlet)
Get app descriptors (main) and associated PID
If PID exists, implicit conclusion that process is running (may be visible or invisible hidden background process w/o UI).
Another related API would be ApplicationManager.getVisibleApplications(), which allows you to list running apps, that are visible (not background services).
As for which are in the background, you will get the process IDs from above, and then you can check those against the current foreground process ID (only one can be in the foreground ... all the others are in the background). Get the foreground process ID from ApplicationManager.getForegroundProcessId()
This code will help you to find out current running applications
ApplicationManager appMan = ApplicationManager.getApplicationManager();
ApplicationDescriptor appDes[] = appMan.getVisibleApplications();
for (int i = 0; i < appDes.length; i++)
{
result = appDes[i].getModuleName();
System.Out.Println("Currently Running application " +result )
}
Related
Does anyone know if there is an API to get the current monitor state (on or off) in Windows (XP/Vista/2000/2003)?
All of my searches seem to indicate there is no real way of doing this.
This thread tries to use GetDevicePowerState which according to Microsoft's docs does not work for display devices.
In Vista I can listen to GUID_MONITOR_POWER_ON but I do not seem to get events when the monitor is turned off manually.
In XP I can hook into WM_SYSCOMMAND SC_MONITORPOWER, looking for status 2. This only works for situations where the system triggers the power off.
The WMI Win32_DesktopMonitor class does not seem to help out as well.
Edit: Here is a discussion on comp.os.ms-windows.programmer.win32 indicating there is no reliable way of doing this.
Anyone else have any other ideas?
GetDevicePowerState sometimes works for monitors. If it's present, you can open the \\.\LCD device. Close it immediately after you've finished with it.
Essentially, you're out of luck—there is no reliable way to detect the monitor power state, short of writing a device driver and filtering all of the power IRPs up and down the display driver chain. And that's not very reliable either.
You could hook up a webcam, point it at your screen and do some analysis on the images you receive ;)
Before doing anything based on the monitor state, just remember that users can use a machine with remote desktop of other systems that don't require a monitor connected to the machine - so don't turn off any visualization based on the monitor state.
You can't.
Look like all monitor power capabilities connected to the "power safe mode"
After searching i found here code that connecting between SC_MONITORPOWER message and system values (post number 2)
I use the code to testing if the system values is changing when i am manually switch off the monitor.
int main()
{
for(;monitorOff()!=1;)
Sleep(500);
return 0;
}//main
And the code is never stopped, no matter how long i am switch off my monitor.
There the code of monitorOff function:
int monitorOff()
{
const GUID MonitorClassGuid =
{0x4d36e96e, 0xe325, 0x11ce,
{0xbf, 0xc1, 0x08, 0x00, 0x2b, 0xe1, 0x03, 0x18}};
list<DevData> monitors;
ListDeviceClassData(&MonitorClassGuid, monitors);
list<DevData>::iterator it = monitors.begin(),
it_end = monitors.end();
for (; it != it_end; ++it)
{
const char *off_msg = "";
//it->PowerData.PD_PowerStateMapping
if (it->PowerData.PD_MostRecentPowerState != PowerDeviceD0)
{
return 1;
}
}//for
return 0;
}//monitorOff
Conclusion : when you manually switch of the the monitor, you cant catch it by windows (if there is no unusual driver interface for this), because all windows capabilities is connected to "power safe mode".
In Windows XP or later you can use the IMSVidDevice Interface.
See
http://msdn.microsoft.com/en-us/library/dd376775(VS.85).aspx
(not sure if this works in Sever 2003)
With Delphi code, you can detect invalid monitor geomerty while standby in progress:
i := 0
('Monitor'+IntToStr(i)+': '+IntToStr(Screen.Monitors[i].BoundsRect.Left)+', '+
IntToStr(Screen.Monitors[i].BoundsRect.Top)+', '+
IntToStr(Screen.Monitors[i].BoundsRect.Right)+', '+
IntToStr(Screen.Monitors[i].BoundsRect.Bottom))
Results:
Monitor geometry before standby:
Monitor0: 0, 0, 1600, 900
Monitor geometry while standby in Deplhi7:
Monitor0: 1637792, 4210405, 31266576, 1637696
Monitor geometry while standby in DeplhiXE:
Monitor0: 4211194, 40, 1637668, 1637693
This is a really old post but if it can help someone, I have found a solution to detect a screen being available or not : the Connecting and Configuring Displays (CCD) API of Windows.
It's part of User32.ddl and the interesting functions are GetDisplayConfigBufferSizes and QueryDisplayConfig. It give us all informations that can be viewed in the Configuration Panel of windows.
In particular the PathInfo contains a TargetInfo property that have a targetAvailable flag. This flag seems to be correctly updated on all the configurations I have tried so far.
This allow you to know the state of every screens connected to the PC and set their configurations.
Here a CCD wrapper for .Net
If your monitor has some sort of built-in USB hub, you could try and use that to detect if the monitor is off/on.
This will of course only work if the USB hub doesn't stay connected when the monitor is consider "off".
I am trying to understand how I shall port my Java chess engine to dart.
So I have understood that I should use an Isolates to run my engine in parallell with the GUI but how can I force the engine to terminate the search.
In java I just set some boolean that where shared between the engine thread and the gui thread.
Answer I got:
You should send a message to the isolate, telling it to stop. You can simply do something like:
port.send('STOP');
My request
Thanks for the clarification. What I don't understand is that if the chess engine isolate is busy due to a port.send('THINK') command how can it respond to a port.send('STOP') command
Each isolate is single-threaded. As long as your program is running nobody else will have the means to interfere with your execution.
If you want to be able to react to outside events (including messages from other isolates) you need to split your long running execution into smaller parts. A chess-engine probably has already some state to know where to look for the next move (assuming it's built with something like A*). In this case you could just periodically interrupt your execution and resume after a minimal timeout.
Example:
var state;
var stopwatch = new Stopwatch()..run();
void longRunning() {
while (true) {
doSomeWorkThatUpdatesTheState();
if (stopwatch.elapsedMilliseconds > 200) {
stopwatch.reset();
Timer.run(longRunning);
return;
}
}
}
The new API will contain a
isolate.kill(loopForever ? Isolate.IMMEDIATE : Isolate.AS_EVENT);
See https://code.google.com/p/dart/issues/detail?id=21189#c4 for a full example.
I use the heart program to restart an Erlang node when it becomes unresponsive. However, I am finding it hard to understand why the node freezes. SASL logs don't show any errors, and my own logs don't seem to show anything remarkable happening at those times. Can anybody give advice on debugging this sort of thing?
By default the heart program issues a SIGKILL to kill off the unresponsive VM so it can quickly start a new one. This makes getting any useful information about the VM pretty much impossible. Something I've tried in the past is to patch the heart program to avoid the hard kill and instead get the VM to create a crash dump and a coredump. I used a patch like this (this one is for Erlang/OTP R14B02):
--- erts/etc/common/heart.c.orig 2011-04-17 12:11:24.000000000 -0400
+++ erts/etc/common/heart.c 2011-04-17 12:12:36.000000000 -0400
## -559,10 +559,11 ##
int res;
if(heart_beat_kill_pid != 0){
pid = (pid_t) heart_beat_kill_pid;
- res = kill(pid,SIGKILL);
+ res = kill(pid,SIGUSR1);
+ sleep(4);
for(i=0; i < 5 && res == 0; ++i){
sleep(1);
- res = kill(pid,SIGKILL);
+ res = kill(pid,i < 2 ? SIGQUIT : SIGKILL);
}
if(errno != ESRCH){
print_error("Unable to kill old process, "
As you can see, with this patch heart will first issue a SIGUSR1 to try to get the VM to create a crash dump. Since this can take awhile, heart then sleeps for 4 seconds. You might have to increase this sleep time if you're not getting full crash dumps. After that, heart then tries twice to issue a SIGQUIT with the hope of getting a coredump, and if that fails, issues a SIGKILL.
Note that this patch will slow down heart's VM restart due to the time required to wait for the crash dumps and coredumps. If you use it in production, be aware of this limitation.
You could try to call erlang:halt/1 from your HEART_COMMAND thus creating a crash dump from the unresponsive node.
You can try using the erl_call tool with e.g. -a erlang halt 123.
If the erlang node can't respond to this is also interesting information.
Did you try increasing `HEART_BEAT_TIMEOUT? Maybe the node is just bogged down a bit an misses the timeout but doesn't freeze.
If you have any idea of why it is freezing you could try to trace the module using dbg.
http://www.erlang.org/doc/man/dbg.html
In short try
dbg:tracer(), dbg:p(all,c), dbg:tpl(Module, Function, x).
If you want to stop this tracing issue
dbg:ctpl()
See documentation for more info.
Note: Change Module and Function to whatever you want to trace, leave x as it is. You can also skip Function and only give Module, x.
Warning: Running this on a live system can be dangerous as the amount of information that is going to be printed to the shell can be enormous.
FATAL ERROR: CALL_AND_RETRY_2 Allocation Failed - process out of memory
I'm seeing this error and not quite sure where it's coming from. The project I'm working on has this basic workflow:
Receive XML post from another source
Parse the XML using xml2js
Extract the required information from the newly created JSON object and create a new object.
Send that object to connected clients (using socket.io)
Node Modules in use are:
xml2js
socket.io
choreographer
mysql
When I receive an XML packet the first thing I do is write it to a log.txt file in the event that something needs to be reviewed later. I first fs.readFile to get the current contents, then write the new contents + the old. The log.txt file was probably around 2400KB around last crash, but upon restarting the server it's working fine again so I don't believe this to be the issue.
I don't see a packet in the log right before the crash happened, so I'm not sure what's causing the crash... No new clients connected, no messages were being sent... nothing was being parsed.
Edit
Seeing as node is running constantly should I be using delete <object> after every object I'm using serves its purpose, such as var now = new Date() which I use to compare to things that happen in the past. Or, result object from step 3 after I've passed it to the callback?
Edit 2
I am keeping a master object in the event that a new client connects, they need to see past messages, objects are deleted though, they don't stay for the life of the server, just until their completed on client side. Currently, I'm doing something like this
function parsingFunction(callback) {
//Construct Object
callback(theConstructedObject);
}
parsingFunction(function (data) {
masterObject[someIdentifier] = data;
});
Edit 3
As another step for troubleshooting I dumped the process.memoryUsage().heapUsed right before the parser starts at the parser.on('end', function() {..}); and parsed several xml packets. The highest heap used was around 10-12 MB throughout the test, although during normal conditions the program rests at about 4-5 MB. I don't think this is particularly a deal breaker, but may help in finding the issue.
Perhaps you are accidentally closing on objects recursively. A crazy example:
function f() {
var shouldBeDeleted = function(x) { return x }
return function g() { return shouldBeDeleted(shouldBeDeleted) }
}
To find what is happening fire up node-inspector and set a break point just before the suspected out of memory error. Then click on "Closure" (below Scope Variables near the right border). Perhaps if you click around something will click and you realize what happens.
The following code throws an exception...
private void EnsureDiskSpace()
{
using (IsolatedStorageFile file = IsolatedStorageFile.GetUserStoreForSite())
{
const long NEEDED = 1024 * 1024 * 100;
if (file.AvailableFreeSpace < NEEDED)
{
if (!file.IncreaseQuotaTo(NEEDED))
{
throw new Exception();
}
}
}
}
But this code does not (it displays the silverlight "increase quota" dialog)...
private void EnsureDiskSpace()
{
using (IsolatedStorageFile file = IsolatedStorageFile.GetUserStoreForSite())
{
const long NEEDED = 1024 * 1024 * 100;
if (file.Quota < NEEDED)
{
if (!file.IncreaseQuotaTo(NEEDED))
{
throw new Exception();
}
}
}
}
The only difference in the code is that the first one checks file.AvailableFreeSpace and the second checks file.Quota.
Are you not allowed to check the available space before requesting more? It seems like I've seen a few examples on the web that test the available space first. Is this no longer supported in SL3? My application allows users to download files from a server and store them locally. I'd really like to increase the quota by 10% whenever the user runs out of sapce. Is this possible?
I had the same issue. The solution for me was something written in the help files. The increase of disk quota must be initiated from a user interaction such as a button click event. I was requesting increased disk quota from an asynchronous WCF call. By moving the space increase request to a button click the code worked.
In my case, if the WCF detected there was not enough space, the silverlight app informed the user they needed to increase space by clicking a button. When the button was clicked, and the space was increased, I called the WCF service again knowing I now had more space. Not as good a user experience, but it got me past this issue.
There is a subtle bug in your first example.
There may not be enough free space to add your new storage, triggering the request - but the amount you're asking for may be less than the existing quota. This throws the exception and doesn't show the dialog.
The correct line would be
file.IncreaseQuotaTo(file.Quota + NEEDED);
I believe that there were some changes to the behavior in Silverlight 3, but not having worked directly on these features, I'm not completely sure.
I did take a look at this MSDN page on the feature and the recommended approach is definitely the first example you have; they're suggesting:
Get the user store
Check the AvailableFreeSpace property on the store
If needed, call IncreaseQuotaTo
It isn't ideal, since you can't implement your own growth algorithm (grow by 10%, etc.), but you should be able to at least unblock your scenario using the AvailableFreeSpace property, like you say.
I believe reading the amount of total space available (the Quota) to the user store could be in theory an issue, imagine a "rogue" control or app that simply wants to fill every last byte it can in the isolated storage space, forcing the user eventually to request more space, even when not available.
It turns out that both code blocks work... unless you set a break point. For that matter, both code blocks fail if you do set a break point.