Returns the current read mode setting.
The I_GRDOPT operation returns the current read mode setting in an int parameter pointed to by the arg parameter. Read modes are described in the read subroutine description.
This operation is part of STREAMS Kernel Extensions.
If unsuccessful, the errno global variable is set to the following value:
| Value | Description |
|---|---|
| EFAULT | The arg parameter points outside the allocated address space. |