[Info-vax] Use of logical names other than I/O redirection

[Bob Gezelter]

On Saturday, September 10, 2022 at 7:35:08 PM UTC-4, alanfe... at gmail.com wrote:
> Greetings. 
> 
> I recall Hoff once lamenting about logical names. He said they are mostly good for I/O redirection. And, IIRC, not liking using them to store application data. 
> 
> I was wondering how people here (esp. Hoff!) feel about their use in batch queues and mail. 
> 
> Just askin'.
Alan,

I generally agree with Dan. Almost twenty years ago, 2004 to be precise, I authored an OpenVMS Technical Journal article entitled "Inheritance Based Environments in Stand-alone OpenVMS Systems and OpenVMS Clusters". It is available on my www site at: http://www.rlgsc.com/publications/vmstechjournal/inheritance.html.

Realtime use to signal status is sometimes seen, and is safe so long as there is a single writer. If there are multiple writers, the classic dangers of multiple modifiers of uninterlocked storage locations apply. At today's speeds, this is an ever more serious hazard. In "Resolving the Contention Problem with ASSIGN/DEFINE" (http://www.rlgsc.com/blog/openvms-consultant/assign-define-contention.html) I proposed the addition of a interlocking /COMPARE:"<string>" qualifier to ASSIGN/DEFINE to transform the underlying $CRELNM system service from a simple assignment to a "Compare&Swap" semantic.

IMHO, the use of logical names for Batch/Print queues and email is a reasonable practice. It is actually the subject of an upcoming column in my "OpenVMS Consultant" series.

- Bob Gezelter, http://www.rlgsc.com