Checks if a given band is writable.
The I_CANPUT operation checks a given priority band to see if it can be written on. The arg parameter contains the priority band to be checked.
The return value is set to one of the following:
| Value | Description |
|---|---|
| 0 | The band is flow controlled. |
| 1 | The band is writable. |
| -1 | An error occurred. |
If unsuccessful, the errno global variable is set to the following value:
| Value | Description |
|---|---|
| EINVAL | The value in the arg parameter is invalid. |