EnumDependentServices

EnumDependentServices

The EnumDependentServices function enumerates services that depend on another specified service; that is, the specified service must be running before the enumerated services can run. The name and status of each dependent service are provided.

BOOL EnumDependentServices(

SC_HANDLE hService,	// handle to service
DWORD dwServiceState,	// state of services to enumerate
LPENUM_SERVICE_STATUS lpServices,	// pointer to service status buffer
DWORD cbBufSize,	// size of service status buffer
LPDWORD pcbBytesNeeded,	// pointer to variable for bytes needed
LPDWORD lpServicesReturned	// pointer to variable for number returned
);

Parameters

hService

Handle that identifies the service. This handle is returned by the OpenService or CreateService function, and it must have SERVICE_ENUMERATE_DEPENDENTS access.

dwServiceState

Specifies the services to enumerate based on their running state. It must be one or both of the following values:

Value	Meaning
SERVICE_ACTIVE	Enumerates services that are in the following states: SERVICE_START_PENDING, SERVICE_STOP_PENDING, SERVICE_RUNNING, SERVICE_CONTINUE_PENDING, SERVICE_PAUSE_PENDING, and SERVICE_PAUSED.
SERVICE_INACTIVE	Enumerates services that are in the SERVICE_STOPPED state.

lpServices

Pointer to an array of ENUM_SERVICE_STATUS structures. Each structure receives name and service status information for a dependent service. The order of the services in this array is the reverse of the start order of the services. In other words, the first dependent service in the array is the one that would be started last, and the last service in the array is the one that would be started first.

cbBufSize

Specifies the size, in bytes, of the buffer pointed to by the lpServices parameter.

pcbBytesNeeded

Pointer to a variable that receives the number of bytes needed to store the array of service entries. The variable only receives this value if the buffer pointed to by lpServices is too small, indicated by function failure and the ERROR_MORE_DATA error; otherwise, the contents of *pcbBytesNeeded are undefined.

lpServicesReturned

Pointer to a variable that receives the number of service entries returned.

Return Values

If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero. To get extended error information, call GetLastError.

Errors

The following error codes may be set by the service control manager. Other error codes may be set by the registry functions that are called by the service control manager.

Value		Meaning
ERROR_ACCESS_DENIED
	The specified handle was not opened with SERVICE_ENUMERATE_DEPENDENTS access.
ERROR_INVALID_HANDLE
	The specified handle is invalid.
ERROR_INVALID_PARAMETER
	A parameter that was specified is invalid.
ERROR_MORE_DATA
	The buffer pointed to by lpServices is not large enough. The function sets the variable pointed to by lpServicesReturned to the actual number of service entries stored into the buffer. The function sets the variable pointed to by pcbBytesNeeded to the number of bytes required to store all of the service entries.

Remarks

The returned services entries are ordered in the reverse order of the start order, with group order taken into account. If you need to stop the dependent services, you can use the order of entries written to the lpServices buffer to stop the dependent services in the proper order.