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Conference azur::mcc

Title:	DECmcc user notes file. Does not replace IPMT.
Notice:	Use IPMT for problems. Newsletter location in note 6187
Moderator:	TAEC::BEROUD

Created:	Mon Aug 21 1989
Last Modified:	Wed Jun 04 1997
Last Successful Update:	Fri Jun 06 1997
Number of topics:	6497
Total number of notes:	27359

4763.0. "AM Environment on Ultrix" by BALZAC::COULON (Even if it works, ask why) Thu Mar 25 1993 05:43

 Two or three questions about the DECmcc Access Module environment on Ultrix:

 1- The AM is started as a subprocess of the enroller... Can you confirm the 
fact that n different Ultrix users will use n AMs subprocesses?

 2- If DECmcc users use the same username, do they share the same AM (MM)? How 
is the communication between MMs working in this case? What happens to pending
operations if one re-enrolls (and therefore kills?) an existing MM?

 3- The MM Programming manual specifies that the MM Init routine populates the
dispatch trees, then the dispatch file table is updated then a system-wide
event is generated to signal a new dispatch table... How is this table used
regarding the userIds, existing MMs, private dispatch tables... I have seen 
note 3843.4 but I'm not sure to fully understand these "ugly details"! My 
(customer's) main concern is about questions 1 and 2!

 Regards,

 Serge

T.R Title User Personal
Name Date Lines

4763.1 Answers 1 & 2 BOEHM::MINTZ Erik Mintz Thu Mar 25 1993 06:11 15

T.R	Title	User	Personal Name	Date	Lines
4763.1	Answers 1 & 2	BOEHM::MINTZ	Erik Mintz	`Thu Mar 25 1993 06:11`	15
	> 1- The AM is started as a subprocess of the enroller... Can you confirm the >fact that n different Ultrix users will use n AMs subprocesses? This is correct. > 2- If DECmcc users use the same username, do they share the same AM (MM)? How >is the communication between MMs working in this case? What happens to pending >operations if one re-enrolls (and therefore kills?) an existing MM? The key is UID. Users with the same UID will share AM processes. Under noral conditions the is a good way to share resources. But it does give the users the ability to step on each other (as in your example of a re-enroll, but in a normal environment re-enrolls are only performed by root anyway).

> 1- The AM is started as a subprocess of the enroller... Can you confirm the 
>fact that n different Ultrix users will use n AMs subprocesses?

This is correct.

> 2- If DECmcc users use the same username, do they share the same AM (MM)? How 
>is the communication between MMs working in this case? What happens to pending
>operations if one re-enrolls (and therefore kills?) an existing MM?

The key is UID.  Users with the same UID will share AM processes.
Under noral conditions the is a good way to share resources.  But it does give
the users the ability to step on each other (as in your example of a re-enroll,
but in a normal environment re-enrolls are only performed by root anyway).