How-to-start-and-stop-a-service-or-get-status


            Title: How to start and stop a service (or get status)
Question: How to use the API functions OpenSCManager, OpenService etc.
Answer:
Here are the functions ServiceStart and ServiceStop:
function ServiceStart(aMachine, aServiceName : string ) : boolean;
// aMachine is UNC path or local machine if left empty
var
 h_manager,h_svc: SC_Handle;
 svc_status: TServiceStatus;
 Temp: PChar;
 dwCheckPoint: DWord;
begin
 svc_status.dwCurrentState := 1;
 h_manager := OpenSCManager(PChar(aMachine), Nil, 
 SC_MANAGER_CONNECT);
 if h_manager 0 then
 begin
 h_svc := OpenService(h_manager, PChar(aServiceName),
 SERVICE_START or SERVICE_QUERY_STATUS);
 if h_svc 0 then
 begin
 temp := nil;
 if (StartService(h_svc,0,temp)) then
 if (QueryServiceStatus(h_svc,svc_status)) then
 begin
 while (SERVICE_RUNNING svc_status.dwCurrentState) do
 begin
 dwCheckPoint := svc_status.dwCheckPoint;
 Sleep(svc_status.dwWaitHint);
 if (not QueryServiceStatus(h_svc,svc_status)) then
 break;
 if (svc_status.dwCheckPoint begin
 // QueryServiceStatus didn't increment dwCheckPoint
 break;
 end;
 end;
 end;
 CloseServiceHandle(h_svc);
 end;
 CloseServiceHandle(h_manager);
 end;
 Result := SERVICE_RUNNING = svc_status.dwCurrentState;
end;
function ServiceStop(aMachine,aServiceName : string ) : boolean;
// aMachine is UNC path or local machine if left empty
var
 h_manager,h_svc : SC_Handle;
 svc_status : TServiceStatus;
 dwCheckPoint : DWord;
begin
 h_manager:=OpenSCManager(PChar(aMachine),nil,
 SC_MANAGER_CONNECT);
 if h_manager 0 then
 begin
 h_svc := OpenService(h_manager,PChar(aServiceName),
 SERVICE_STOP or SERVICE_QUERY_STATUS);
 if h_svc 0 then
 begin
 if(ControlService(h_svc,SERVICE_CONTROL_STOP,
 svc_status))then
 begin
 if(QueryServiceStatus(h_svc,svc_status))then
 begin
 while(SERVICE_STOPPED svc_status.dwCurrentState)do
 begin
 dwCheckPoint := svc_status.dwCheckPoint;
 Sleep(svc_status.dwWaitHint);
 if(not QueryServiceStatus(h_svc,svc_status))then
 begin
 // couldn't check status
 break;
 end;
 if(svc_status.dwCheckPoint break;
 end;
 end;
 end;
 CloseServiceHandle(h_svc);
 end;
 CloseServiceHandle(h_manager);
 end;
 Result := SERVICE_STOPPED = svc_status.dwCurrentState;
end;
To get the status you need:
function ServiceGetStatus(sMachine, sService: string ): DWord;
var
 h_manager,h_service: SC_Handle;
 service_status : TServiceStatus;
 hStat : DWord;
begin
 hStat := 1;
 h_manager := OpenSCManager(PChar(sMachine) ,Nil, 
 SC_MANAGER_CONNECT);
 if h_manager 0 then
 begin
 h_svc := OpenService(h_manager,PChar(sService),
 SERVICE_QUERY_STATUS);
 if h_svc 0 then
 begin
 if(QueryServiceStatus(h_svc, service_status)) then
 hStat := service_status.dwCurrentState;
 CloseServiceHandle(h_svc);
 end;
 CloseServiceHandle(h_manager);
 end;
 Result := hStat;
end;
It's returning one of the following constant's:
SERVICE_STOPPED
SERVICE_RUNNING
SERVICE_PAUSED
SERVICE_START_PENDING
SERVICE_STOP_PENDING
SERVICE_CONTINUE_PENDING
or
SERVICE_PAUSE_PENDING
What you need is the unit WinSvc !
Examples Delphi
