QueryServiceConfigA function (winsvc.h)

Article
02/09/2023

Retrieves the configuration parameters of the specified service. Optional configuration parameters are available using the QueryServiceConfig2 function.

Syntax

BOOL QueryServiceConfigA(
  [in]            SC_HANDLE               hService,
  [out, optional] LPQUERY_SERVICE_CONFIGA lpServiceConfig,
  [in]            DWORD                   cbBufSize,
  [out]           LPDWORD                 pcbBytesNeeded
);

Parameters

[in] hService

A handle to the service. This handle is returned by the OpenService or CreateService function, and it must have the SERVICE_QUERY_CONFIG access right. For more information, see Service Security and Access Rights.

[out, optional] lpServiceConfig

A pointer to a buffer that receives the service configuration information. The format of the data is a QUERY_SERVICE_CONFIG structure.

The maximum size of this array is 8K bytes. To determine the required size, specify NULL for this parameter and 0 for the cbBufSize parameter. The function will fail and GetLastError will return ERROR_INSUFFICIENT_BUFFER. The pcbBytesNeeded parameter will receive the required size.

[in] cbBufSize

The size of the buffer pointed to by the lpServiceConfig parameter, in bytes.

[out] pcbBytesNeeded

A pointer to a variable that receives the number of bytes needed to store all the configuration information, if the function fails with ERROR_INSUFFICIENT_BUFFER.

Return value

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.

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

Return code	Description
ERROR_ACCESS_DENIED	The handle does not have the SERVICE_QUERY_CONFIG access right.
ERROR_INSUFFICIENT_BUFFER	There is more service configuration information than would fit into the lpServiceConfig buffer. The number of bytes required to get all the information is returned in the pcbBytesNeeded parameter. Nothing is written to lpServiceConfig.
ERROR_INVALID_HANDLE	The specified handle is invalid.

Remarks

The QueryServiceConfig function returns the service configuration information kept in the registry for a particular service. This configuration information is first set by a service control program using the CreateService function. This information may have been updated by a service configuration program using the ChangeServiceConfig function.

If the service was running when the configuration information was last changed, the information returned by QueryServiceConfig will not reflect the current configuration of the service. Instead, it will reflect the configuration of the service when it is next run. The DisplayName key is an exception to this. When the DisplayName key is changed, it takes effect immediately, regardless of whether the service is running.

Examples

For an example, see Querying a Service's Configuration.

Note

The winsvc.h header defines QueryServiceConfig as an alias which automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.

Requirements

Requirement	Value
Minimum supported client	Windows XP [desktop apps only]
Minimum supported server	Windows Server 2003 [desktop apps only]
Target Platform	Windows
Header	winsvc.h (include Windows.h)
Library	Advapi32.lib
DLL	Advapi32.dll

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