niRFSA_GetAttributeViInt64
ViStatus = niRFSA_GetAttributeViInt64 (ViSession vi, ViConstString channelName, ViAttr attributeId, ViInt64 *value);
Purpose
Queries the value of a ViInt64 attribute.
You can use this low-level function to get the values of inherent IVI attributes, class-defined attributes, and instrument-specific attributes. If the attribute represents an instrument state, this function performs instrument I/O in the following cases:
- State caching is disabled for the entire session or for the particular attribute.
- State caching is enabled, and the currently cached value is invalid.
Parameters
Input | ||
Name | Type | Description |
vi | ViSession | Identifies your instrument session. vi is obtained from the niRFSA_init or the niRFSA_initWithOptions functions and identifies a particular instrument session. |
channelName | ViConstString | If the attribute is channel based, this parameter specifies the channel to which the attribute applies. If the attribute is not channel based, set this parameter to "" (empty string) or VI_NULL. |
attributeID | ViAttr | Pass the ID of an attribute. |
Output | ||
Name | Type | Description |
attributeValue | ViInt32* | Returns the current value of the attribute. Pass the address of a ViInt32 variable. |
Return Value
Name | Type | Description | ||
status | ViStatus | Returns the status code of this operation. The status code either indicates success or describes an error or warning condition. You examine the status code from each call to an instrument driver function to determine if an error occurred. To obtain a text description of the status code, call the niRFSA_error_message function. To obtain additional information about the error condition, call the niRFSA_GetError function. To clear the error information from the driver, call the niRFSA_ClearError function. The general meaning of the status code is as follows:
|
Meaning | |
---|---|---|---|---|
0 | Success | |||
Positive Values | Warnings | |||
Negative Values | Errors |