Specifications

System Macros Invoked by Drivers

IFNORD, IFNOWRT, IFRD, IFWRT

Example

MOVZWL $SS_ACCVIO,R0 ;Assume read access failure

MOVL ENTRY_LIST(AP),R11 ;Get address of entry point list

IFRD #4*4,(R11),50$ ;Branch forward if process

; has read access

BRW ERROR ;Otherwise stop with error

The connect-to-interrupt driver uses the IFRD macro to verify that the process

has read access to the four longwords that make up the entry point list. The

address of the entry point list was speciﬁed in the p2 argument of the $QIO

request to the driver.

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