Function get_device_handle 

pub fn get_device_handle(devlabel: u8) -> Status

Get global identifier for a given device label

Usage

This syscall set the device handle that matches the given label in the SVC_EXCHANGE area if the label is found in the kernel declared device list.

If no handle is found, the resulting status is Status::Invalid. If the requested device not in own by the caller, Status::Denied is returned. In these cases, the SVC_EXCHANGE area is not set.