EXE(.exe) still appears in process list, though the service destroyed.

[sp0987 0]

Hi,

 

We have a windows service sample application developed using D11. Observed that even after the service destroyed, the executable still showing in the background for 20sec's. 

When looked for help i found this

 

"When a Windows service is destroyed , the service itself is removed from the running processes, but the executable file (.exe) might still appear in the process list because the underlying process hosting the service (often "svchost.exe") remains running, even if it no longer actively manages the service you deleted; essentially, the executable is still in memory but is not actively performing any service-related functions".

 

Though it's a zombie exe, but still when we run the same exe multiple times , we could able to see the more than one zombie exe's in the process tab in task manager. 

 

 

[David Heffernan 2379]

Do you have a question?

[DelphiUdIT 209]

@sp0987

And, what are your needs ?

 

If the service maintain the zombies for some seconds ... it is so, but really I never see this. When I stop a service the EXE disappear from task manager (of course, if the application has no pending things like threads waiting).

 

If you want that the same exe doesn't run more then one time, use a mutex at the start of the application:

 

var
  hMutex: THandle;

// Creates a unique synchronized object in the operating system
hMutex:=CreateMutex(Nil,False,'Global\MyApplication');
// Checks that the object is not already 'owned' by some other process (program instance),
// in which case exits the program
if (WaitForSingleObject(hMutex,0) = wait_TimeOut) then
  exitprocess(255);

 

 

[sp0987 0]

Am sorry...

1 hour ago, sp0987 said:

"When a Windows service is destroyed , the service itself is removed from the running processes, but the executable file (.exe) might still appear in the process list because the underlying process hosting the service (often "svchost.exe") remains running, even if it no longer actively manages the service you deleted; essentially, the executable is still in memory but is not actively performing any service-related functions".

As per this was it ok for the exe to stay in the background for a period of time?

[DelphiUdIT 209]

I don't know where you catch those info.

Like I told, my experience, I nevere see an executable (service or not service) stay live after "termination".

 

In my developer machine runs only basic services, and i start and stop programmatically the services that I need project based (normally 4/5 services for 4 times per days).

 

May be is a "design basis" by Windows for some kinds of executables or (more likely) some thread or method of the executable is "hanging".

20 seconds is historically the standard timeout within which a closing service is killed by the system, if it does not terminate itself (I remember a value like "KillServiceTimeout" in the registry that keeps the default time, but it could be called something different).