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srv_paramset (Extended Stored Procedure API)

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Applies to: SQL Server

Important

This feature will be removed in a future version of SQL Server. Avoid using this feature in new development work, and plan to modify applications that currently use this feature. Use CLR integration instead.

Sets the value of a remote stored procedure call return parameter. This function has been superseded by the srv_paramsetoutput function.

Syntax

  
int srv_paramset (  
SRV_PROC *  
srvproc  
,  
int  
n  
,   
void *  
data  
,  
int  
len   
);

Arguments

srvproc
Is a pointer to the SRV_PROC structure that is the handle for a particular client connection (in this case, the handle that received the remote stored procedure call). The structure contains information the Extended Stored Procedure API library uses to manage communication and data between the application and the client.

n
Indicates the number of the parameter to set. The first parameter is 1.

data
Is a pointer to the data value to be sent back to the client as the remote stored procedure return parameter.

len
Specifies the actual length of the data to be returned. If the data type of the parameter is of a constant length and does not allow null values (for example, srvbit or srvint1), len is ignored.

Returns

SUCCEED if the parameter value was successfully set; otherwise, FAIL. FAIL is returned when there is no current remote stored procedure, when there is no nth remote stored procedure parameter, when the parameter is not a return parameter, and when the len argument is not legal.

If lenis 0, it returns NULL. Setting len to 0 is the only way to return NULL to the client.

This function returns the following values, if the parameter is one of Microsoft SQL Server 2005 (9.x) data types.

New data types Return data length
BITN NULL: len = 0, data = IG, RET = 0

ZERO: N/A

>=255: N/A

<255: N/A
BIGVARCHAR NULL: len = 0, data = IG, RET = 1

ZERO: len = IG, data = IG, RET = 0

>=255: len = max8k, data = valid, RET = 0

<255: len = <8k, data = valid, RET = 1
BIGCHAR NULL: len = 0, data = IG, RET = 1

ZERO: len = IG, data = IG, RET = 0

>=255: len = max8k, data = valid, RET = 0

<255: len = <8k, data = valid, RET = 1
BIGBINARY NULL: len = 0, data = IG, RET = 1

ZERO: len = IG, data = IG, RET = 0

>=255: len = max8k, data = valid, RET = 0

<255: len = <8k, data = valid, RET = 1
BIGVARBINARY NULL: len = 0, data = IG, RET = 1

ZERO: len = IG, data = IG, RET = 0

>=255: len = max8k, data = valid, RET = 0

<255: len = <8k, data = valid, RET = 1
NCHAR NULL: len = 0, data = IG, RET = 1

ZERO: len = IG, data = IG, RET = 0

>=255: len = max8k, data = valid, RET = 0

<255: len = <8k, data = valid, RET = 1
NVARCHAR NULL: len = 0, data = IG, RET = 1

ZERO: len = IG, data = IG, RET = 0

>=255: len = max8k, data = valid, RET = 0

<255: len = <8k, data = valid, RET = 1
NTEXT NULL: len = IG, data = IG, RET = 0

ZERO: len = IG, data = IG, RET = 0

>=255: len = IG, data = IG, RET = 0

<255: len = IG, data = IG, RET = 0
RET = Return value of srv_paramset
IG = Value will be ignored
valid = Any valid pointer to data

Remarks

Parameters contain data passed between clients and the application with remote stored procedures. The client can specify certain parameters as return parameters. These return parameters can contain values that the Open Data Services server application passes back to the client. Using return parameters is analogous to passing parameters by reference.

You cannot set the return value for a parameter that wasn't invoked as a return parameter. You can use srv_paramstatus to determine how the parameter was invoked.

This function sets the return value for a parameter but it does not actually send the return value to the client. All return parameters, whether their return values have been set with srv_paramset or not, are automatically sent to the client when srv_senddone is called with the status flag SRV_DONE_FINAL set.

When a remote stored procedure call is made with parameters, the parameters can be passed either by name or by position (unnamed). If the remote stored procedure call is made with some parameters passed by name and some passed by position, an error occurs. The SRV_RPC handler is still called, but it appears as if there were no parameters, and srv_rpcparams returns 0.

Important

You should thoroughly review the source code of extended stored procedures, and you should test the compiled DLLs before you install them on a production server. For information about security review and testing, see this Microsoft Web site.

See Also

srv_paramsetoutput (Extended Stored Procedure API)