Specifications

System Macros Invoked by Drivers
READ_SYSTIME
READ_SYSTIME
Reads the current system time.
Format
READ_SYSTIME dst
Parameter
dst
Quadword into which the macro inserts the system time.
Description
The READ_SYSTIME macro generates the code required to obtain a consistent
copy of the system time from EXE$GQ_SYSTIME.
Use of the READ_SYSTIME macro is subject to the following restrictions:
• IPL must be less than 23.
• The processor must be executing in kernel mode.
• When using the macro within pageable program sections (or within code
executing at IPL 2 and below), you must ensure that the pages involved are
locked in memory.
Example
READ_SYSTIME R0
The READ_SYSTIME macro inserts the current system time in R0 and R1.
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