From:	MERC::"uunet!WKUVX1.BITNET!MacroMan" 17-NOV-1992 01:45:28.85
To:	MACRO32@WKUVX1.BITNET
CC:	mwk.uucp@uunet.uu.net!gleason, GAVRON@IT.SUNQUEST.COM
Subj:	RE: Locking down a structure in C

Date sent:  16-NOV-1992 23:36:41



>  Here's another Open VMS Alpha AXP internals C question...
...
>  Now, I'm trying to use a structure...
>
>        static struct
>                {
>                int l_zeep
>                int l_zap
>                int l_zip
>                } zzz ;
>
>  What would be the "best" way to "calculate" the address of the ends of
>  structures to place in a range array for calling sys$lkwset?

Since C structures by definition are contiguous (thanks for the
proof, Bruce!) you know that it is of sizeof(zzz) and at address
zzz.

Therefore given a lock function that locks pages between addresses
1 and 2,
        lock(&zzz,(char *)(&zzz+(char *)sizeof(zzz)));
should work...

>
>Lee K. Gleason N5ZMR
>Control-G Consultants
>gleason@mwk.uucp


Ehud

--
Ehud Gavron        (EG76)
gavron@vesta.sunquest.com                                       This was sent
"The world bores you when you're cool."                         from an Alpha