viBufWrite
Purpose
Writes data to a formatted I/O write buffer synchronously.
C Syntax
ViStatus viBufWrite(ViSession vi, ViBuf buf, ViUInt32 count, ViPUInt32 retCount)
Visual Basic Syntax
viBufWrite&(ByVal vi&, ByVal buf$, ByVal count&, retCount&)
Resource Classes
GPIB INSTR, GPIB INTFC, GPIB-VXI INSTR, Serial INSTR, TCPIP INSTR, TCPIP SOCKET, USB INSTR, USB RAW, VXI INSTR, VXI SERVANT
Parameters
| Name | Direction | Description |
|---|---|---|
|
vi |
IN |
Unique logical identifier to a session. |
|
buf |
IN |
Location of a block of data. |
|
count |
IN |
Number of bytes to be written. |
|
retCount |
OUT |
Number of bytes actually transferred. |
Return Values
| Completion Codes | Description |
|---|---|
|
VI_SUCCESS |
Operation completed successfully. |
| Error Codes | Description |
|---|---|
|
VI_ERROR_INV_OBJECT |
The given session reference is invalid. |
|
VI_ERROR_NSUP_OPER |
The given vi does not support this operation. |
|
VI_ERROR_RSRC_LOCKED |
Specified operation could not be performed because the resource identified by vi has been locked for this kind of access. |
|
VI_ERROR_TMO |
Timeout expired before operation completed. |
|
VI_ERROR_INV_SETUP |
Unable to start write operation because setup is invalid (due to attributes being set to an inconsistent state). |
|
VI_ERROR_IO |
An unknown I/O error occurred during transfer. |
Description
The viBufWrite() operation is similar to viWrite() and does not perform any kind of data formatting. It differs from viWrite() in that the data is written to the formatted I/O write buffer—the same buffer used by viPrintf() and related operations—rather than directly to the device. You can intermix this operation with viPrintf(), but you should not mix it with viWrite().
If this operation returns VI_ERROR_TMO, the write buffer for the specified session is cleared.
VI_NULL is a special value for the retCount parameter. If you pass VI_NULL for retCount, the number of bytes transferred is not returned. You may find this useful if you need to know only whether the operation succeeded or failed.
Related Topics