From:	CRDGW2::CRDGW2::MRGATE::"SMTP::CRVAX.SRI.COM::RELAY-INFO-VAX"  4-JAN-1991 22:30:27.77
To:	MRGATE::"ARISIA::EVERHART"
CC:	
Subj:	File id's and a patch for CSWING

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Date: 4 Jan 91 14:39:00 CST
From: "Harry Flowers" <flowers@memstvx1.memst.edu>
Subject: File id's and a patch for CSWING
To: "info-vax" <info-vax@sri.com>

>From:     adelman@TGV.COM (Kenneth Adelman)
>    In a bound-volume RVN of 0 means "same volume".  An RVN of 0 found
>in a .DIR file means that the file is located on the same volume as
>the directory file is.

Thanks for all the replies about FIDs.  As mentioned, the directory file
contains a zero for the RVN when the file resides on the same volume as the
directory.  The following is a patch for CSWING file SWING_31.C which will
work with bound volume sets.  Just insert the lines with ">new" between the
">old" lines (don't delete the old ones).  It should work for both v3.2 and
v3.2.x (.2 includes more, etc.) modified versions.

>old                    version = buffer[i];
>old                    fid[0] = buffer[i+1];
>old                    fid[1] = buffer[i+2];
>old                    fid[2] = buffer[i+3];
>new                    /*
>new                    ** Patch to handle volume sets
>new                    */
>new                    if (fid[2] == 0) fid[2] = n->fid[2];    
>old                    /*
>old                    **  advance ready for next info
>old                    */
>old                    i += 4;

Hopefully, those currently keeping CSWING updated will incorporate this patch
into their versions.  It may not be robust enough in the case where the extra
byte of the RVN word is used for the extension of the header sequence number,
but the volumes I was checking did not have that many headers.  In that case,
fid[2] would be non-zero, but the RVN byte could be.  The handling of extension
headers seemed to work okay as is.

.__  __.  .___.  ._. ._. Harry Flowers, Tech Support, Memphis State University
|  \/  | / ____\ | | | | 112 Admin Building | Domain: FLOWERS@MSUVX1.MEMST.EDU
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