Re: [PATCH] unified SysV and POSIX mqueues - complete rewrite

[Peter Waechtler <pwaechtler@mac.com>]

Am Dienstag, 26. November 2002 10:12 schrieb Michal Wronski:
> I have a few remarks/questions:
>
> 1. I can't find unregister_filesystem in your patch

I removed the unused code. I can't have a module
with it's own syscalls - posixmsg can't be a module for that reason.

> 2. You have different MQ_PRIO_MAX in library and patch.

Umh, the value is really arbitrary. Could be something like MAX_INT -1

> 3. Does mq_unlink work in a proper way?

I do think so. Did you test it and found a bug?
The vfs keeps track of a reference count. Only when the usage count
of the inode drops to zero, the mqueue_release is called. 
I tested it and it worked.
Even when there is a process in mq_receive() waiting, only the name
is removed as you expect it with unix filesystem semantics. SuSv3
explicitly allows that:

"Calls to mq_open() to recreate the message queue may fail until the message 
queue is actually removed. However, the mq_unlink() call need not block until 
all references have been closed; it may return immediately."