Allows the caller to verify that the SCSI adapter device driver to which this device instance is attached supports gathered writes.
This operation allows the caller to verify that the gathered write function is supported by the SCSI adapter device driver before the caller attempts such an operation. The SCIOGTHW operation fails if a SCSI adapter device driver does not support gathered writes.
The arg parameter to the SCIOGTHW operation is set to null by the caller to indicate no input parameter is passed.
Note: This operation is not supported by all SCSI I/O Controllers. If not supported, errno is set to EINVAL and a value of -1 is returned.
When completed successfully, the SCIOGTHW operation returns a value of 0, meaning gathered writes are supported. Otherwise, a value of -1 is returned and errno global variable is set to EINVAL.
SCSI Adapter device driver.