IPC facilities (shared memory)

[Dominick Samperi]

In article <9844 at steinmetz.steinmetz.UUCP> davidsen at crdos1.UUCP (bill davidsen) writes:
>
>  SysV shared memory segments are inherited by the child, like any other
>open handle. If you open the segment and then do a fork, the child has
>access. If you fork and then open, the child will have to open, too.
>
>-- 
>	bill davidsen		(wedu at ge-crd.arpa)
>  {uunet | philabs | seismo}!steinmetz!crdos1!davidsen
>"Stupidity, like virtue, is its own reward" -me

Perhaps you are talking about the Xenix-style IPC facilities here (sgget, etc.)
which I no nothing about. When the SysV-style facilities are used a forked
child process must attach a shared memory segment (using the segment identifier
that the parent got when it created the segment) before it can use it. This
works fine on an AT&T 3b2 and under Microport's System V/AT, but the child gets
an "invalid argument" error under SCO Xenix (same source code used on each
system, compiled with -Mle in the Xenix environment).
-- 
Dominick Samperi, Manhattan College, NYC
    manhat!samperi at NYU.EDU           ihnp4!rutgers!nyu.edu!manhat!samperi
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