Michael Anderson writes:

>I have found that using the POSIX shell I can install a new version of an
>application while it is being used/loaded by one or more users. MPE would
>never allow this!
>
>For example, my Sales Branch application.
>------------
>:RENAME SBR0000,SBR0000O
>EXCLUSIVE VIOLATION: FILE BEING ACCESSED  (FSERR 90)
>Open failed on file "SBR0000.BRANCH.TIW".  Not renamed. (CIERR 372)
>------------
>
>However in POSIX I can:
>
>---------------------
>> mv SBR0000 SBR0000O
>> mv SBR0000N SBR0000
>>---------------------
>
>I kinda like the idea of bypassing the need to log users off the system to do
>this, but then I make some people around here (TIW) nervous.

One other difference between these two is that the :RENAME command
updates the file's access and modify times. The Posix mv command does
not. So in this case, you won't be able to look at the file's modify
timestamp to see when it was moved into place.

-- Bruce


--------------------------------------------------------------------------
Bruce Toback    Tel: (602) 996-8601| My candle burns at both ends;
OPT, Inc.            (800) 858-4507| It will not last the night;
11801 N. Tatum Blvd. Ste. 142      | But ah, my foes, and oh, my friends -
Phoenix AZ 85028                   | It gives a lovely light.
[log in to unmask]                   |     -- Edna St. Vincent Millay