From owner-freebsd-hackers  Wed Jan 29 06:58:48 1997
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Date: Wed, 29 Jan 1997 17:01:00 +0000
From: Meir Dukhan <mdukhan@bis.co.il>
Organization: Bis Software Systems Ltd
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To: Julian Elischer <julian@whistle.com>
CC: hackers@freebsd.org, mdukhan@quasi.bis.co.il
Subject: Re: Sys V IPC
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Thanks for your answer Julian, 
and let me ask/precise a little bit,

Julian Elischer wrote:
> 
> Meir Dukhan wrote:
> >
> > Hi
> >`
> > Ok, I know BSD ppl may not like it, but anyway I have few questions I
> > think some of you know the answers.
> >
> > Sys V ipc (at least the calls related to shared mem and messages queues)
> > seems to _not_ be implemented as system calls.
> >
> > Indeed, ktrace/kdump wont records them as system calls (even if the
> > manpage for shmat is in section 2 ;=)
> they are system calls
> you need to enable them in your kernel config.
> they are not compiled in to GENERIC.

That's was not what I wanted to say. First my GENERIC file has the 
SYSVSHM, SYSVSEM, SYSVMSG options. and second I work with a kernel that
has, too, these options enabled. 

By saying that they are not sys call, I mean that maybe they are not
implemented as system calls, because ktrace doesn't record them . 

Another possibility is that ktrace is not aware that msgrcv/msgsnd,
shmget/shmat and freinds _are_ system calls.

I don't know how ktrace works, maybe it make its jobs by looking at a
table of existing system calls, instead of checking if a call is
actually a system call or a mere function. 

> >
> > - a process can have no more than 8 shared mem segments
> > (how can I change this ?)
> 
> compile in a bigger number?

Where can I specify this number ?

Can one confirm/infirm  ?
Tia

-- Meir

ps: cc to mdukhan@bis.co.il, I'm not on hackers@freebsd.org, Thanks to
all in advance.