[Info-vax] Stupid question of the day, re: OpenVMS process names

[Arne Vajhøj]

On 3/13/2020 10:18 AM, Bob Gezelter wrote:
> On Friday, March 13, 2020 at 10:10:04 AM UTC-4, Tim Lovern wrote:
>> On Friday, March 13, 2020 at 7:07:26 AM UTC-7, Arne Vajhøj wrote:
>>> On 3/13/2020 9:55 AM, Tim Lovern wrote:
>>>> Ok, I cannot have two processes with the same process name, but I can
>>>> set my process name to be the same as that of a different user.
>>>>
>>>> I get that process names are not guaranteed to be unique. So what is
>>>> actually happening behind the curtain? is the process name hashed
>>>> with the UIC internally, and this is what prevents me from having two
>>>> identically named processes but allows me to have the same name as
>>>> somebody else's process?
>>>>
>>>> Or is it some other mechanism that I probably understood at one time
>>>> but have long since managed to forget? (finite number of brain cells,
>>>> infinite volumes of adult beverages, you do the math... :-) )
>>>
>>> Process names has to be unique within processes belonging
>>> to users in same *group*.
>>
>> So it is the UIC (group) driving it. I thought so, but couldn't remember.
> 
> Reference IDSM.
> 
> Not hashed, effectively prefixed.

That one is pretty clear.

1.5 edition page 442:

"... If no other process in the same group has the same name,
... places the new name in PCB at offset PCB$T_LNAME ..."

It is also in Programming Concets Manual.

8.4 section 4.1.2:

"A process name is a 1- to 15-character name string. Each process name 
must be unique within its group (processes in different groups can have 
the same name). "

Arne