AIFDEVICEGET

Returns characteristics for devices.

Syntax

                     REC          I32A         I64A

 AIFDEVICEGET (overall_status, itemnum_array, item_array,



                     I32A       I32       REC

               itemstatus_array,  ldev,  device_key,



                 I32

               user_id);

Parameters

overall_status

record by reference (required)

Returns the overall status of the call. A zero indicates a successful call. A negative value indicates an error in the overall call, not specific to any particular item. A positive value indicates the last element in itemstatus_array, signaling an error condition. Refer to appendix A for meanings of status values.

Record type: status_type (Refer to appendix B.)

itemnum_array

32-bit signed integer array by reference (required)

An array of integers where each element is an item number indicating the information to be returned to a data structure pointed to in the corresponding element in item_array. If n item numbers are being requested, element n+1 must be a zero to indicate the end of the element list.

item_array

64-bit address array by reference (required)

An array where each element is a 64-bit address pointing to a data structure where information is returned. Information and its required data type are defined by the item number passed in the corresponding element in itemnum_array.

Array type: globalanyptr

itemstatus_array

record array by reference (required)

An array where each element returns the status of the operation performed in the corresponding element in item_array. A zero indicates a successful operation. A negative value indicates an error condition. A positive value indicates a warning. Refer to appendix A for meanings of status values.

Array type: status_type (Refer to appendix B.)

ldev

32-bit signed integer by reference (optional)

The logical device number for the request.

device_key

record by reference (optional)

The ufid for the device file.

user_id

32-bit signed integer by value (optional)

The user ID assigned to a vendor at the time of purchase of the Architected Interface Facility: Operating System product. If it is not passed, the caller must have previously called AIFACCESSON.

Default: 0

Operation Notes

The AIFDEVICEGET call requires ldev or device_key, which specify the requested device. Both ldev and device_key can be obtained by calling the AIFSYSWIDEGET procedure area 13000. Items are divided into four classes: system tables, terminals, disks, and tape drives. In most cases, the device must be configured in order to return item values.

All device control functions (for items 13100-13399) are queued and processed serially. For a device with an outstanding I/O request, the control function request from the AIF device call is not processed until the pending I/O is complete.

If the device is a terminal, the AIF call is processed after either the pending read is complete or the terminal read times out.

The AIF device control terminal functions (13101-13138) do not guarantee the behavior is the same for all types of terminal connections. The behavior is highly dependent on the low-level drivers and type of connection. The items are not guaranteed to work for all connection types since the functionality may not be supported in the lower level drivers. For more information on the behavior of the various terminal connections see the Asynchronous Serial Communications Programmer's Reference Manual (32022-61001).

The AIFs perform many of the same operations as FCONTROL and FDEVICECONTROL. They do not provide capabilities that are not already available through these interfaces. On MPE/iX Release 5.0 there are performance improvements to the FCONTROL and FDEVICECONTROL paths for DTC terminal connections that are not available through the I/O interfaces used by the AIFs. Therefore, the recommendation is to use the DTC terminal control functions provided by FCONTROL and FDEVICECONTROL on Release 5.0 and later.

Many of the device control functions can only occur while the device is open. If the caller does not have the device open, it will be opened on the caller's behalf. However, the device opened by the AIF is closed before returning to the caller. This often returns the device to the settings it had prior to the open. For the device to maintain the settings it should be opened and closed by the caller.

AIFDEVICEGET

Technical documentation

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Syntax

Parameters

Operation Notes