Legacy Document

Inside Macintosh: Devices /

Chapter 1 - Device Manager / Device Manager Reference

Device Manager Functions / Writing and Installing Device Drivers

IODone

You use the IODone routine to notify the Device Manager that an I/O request has completed.

DESCRIPTION

The IODone routine sets the ioResult field of the parameter block with the value returned by the driver in register D0. It then removes the current request from the driver I/O queue and marks the driver inactive. If there are no pending requests, and the dNeedLock bit of the dCtlFlags word is not set, IODone unlocks the driver and its device control entry. Finally, IODone executes the completion routine, if any.

The section "Entering and Exiting From Driver Routines," beginning on page 1-29, explains when to use this routine.

ASSEMBLY-LANGUAGE INFORMATION

Registers on entry
A1	Pointer to DCE
D0	Result code

Jump vector
JIODone

SEE ALSO

For an example of how to call the IODone routine from an assembly-language dispatching routine, see Listing 1-8 on page 1-29.