On Dec 15, 2:41 am, s...@antinode.org (Steven M. Schweda) wrote:
> When I use the C RTL open() to open a file, I can specify "ctx=stm",
> which, according to the HELP, "Forces stream mode access". I'd be
> grateful if someone could tell me what, if anything, this does to the
> FAB, RAB, or any other RMS structure.

It tells the CRTL to go ahead and use NON RMS byte access.
The CRTL then uses RMS SYS$READ and SYS$WRITE calls to do BLOCKIO to
the file and interprets the record structure itself.

What it does to the RAB and FAB is best observed using ANALYZE/
SYSTEM ... SET PROC ... SHOW PROC/RMS=(RAB,FAB,FSB)

The FSB is the statistics block which of course will only be there if
you have done a SET FILE/STATS before the open.

hth,
Hein.





(I'd like to be able to fiddle
> with this setting in an access callback function, but I don't know what
> it does where.)
>
> ------------------------------------------------------------------------
>
> Steven M. Schweda sms@antinode-org
> 382 South Warwick Street (+1) 651-699-9818
> Saint Paul MN 55105-2547