Specifications

Operating System Routines
EXE$MODIFY
• If MMG$IOLOCK fails, it returns SS$_ACCVIO, SS$_INSFWSL, or page
fault status to EXE$MODIFYLOCKR.
If either EXE$READCHKR or MMG$IOLOCK returns an error status other than
a page fault condition, EXE$MODIFYLOCKR calls EXE$ABORTIO. In the event
of a page fault, EXE$MODIFYLOCKR adjusts direct I/O count and AST count to
the values they held before the I/O request, deallocates the IRP, and restarts the
I/O request at the $QIO system service. This procedure is carried out so that the
user process can receive ASTs while it waits for the page fault to complete. Once
the page is faulted into memory, the $QIO system service will resubmit the I/O
request.
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