Article 166988 of comp.os.vms:
On 3 Apr 1997 00:03:29 GMT, mathog@seqaxp.bio.caltech.edu wrote:

>Wouldn't it be nice if there was a special "fan in" mailbox?  Every time it
>was read the result would be both a record AND the PID of the
>process that wrote it.  (It might also be useful to let a process write
>to this type of mailbox and set the "PID" it wants to be seen.)  Something
>like this simple pseudocode: 

The IOSB for mailbox I/O does this. On the completion of a write the
IOSB contains the PID of the reader. On the completion of a read, the
IOSB contains the PID of the writer.

>The conjugate "fan out" mailbox could take several different forms.  One I
>like is a set of output queues for N processes at once, where the fan out
>mailbox holds one or more records for each process specified, like this: 

I don't see much benefit in this over having separate mailboxes. If
you want to hide this in the subroutine that spawns the subprocess, it
would all be transparent.

-- 
Reece R. Pollack
Senior Software Engineer
Attachmate Open Systems Group