OpenDevice

open a trackdisk unit

Grands access to a specific unit of the trackdisk.device

iORequest

an I/O Request Block that the Open routine should initialize.

UnitNumber

a number between 0 and 3, identifying the drives 0 to 3.

Flags

TDF_ALLOW_NON_3_5: If this flag is set, then the trackdisk.device also opens 5.25" devices otherwise, such drives remain invisible.

0 for success, or an error code from <exec/errors.h>

<devices/trackdisk.h>, <exec/errors.h>

If the unit was already opened anytime before the Flags are ignored and OpenDevice always succeeds.