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From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: Alan Stern <stern@rowland.harvard.edu>
Subject: Re: [PATCH 2/8] PM: suspend_block: Add driver to access suspend blockers from user-space
Date: Mon, 3 May 2010 17:03:11 +0200
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On Sunday 02 May 2010, Alan Stern wrote:
> On Sun, 2 May 2010, Rafael J. Wysocki wrote:
> 
> > Hmm.  It doesn't seem to be possible to create two different suspend blockers
> > using the same file handle.  So, what exactly is a process supposed to do to
> > use two suspend blockers at the same time?
> 
> Open the file twice, thereby obtaining two file handles.

Well, that's what I thought.

I must admit I'm not really comfortable with this interface.  IMO it would
be better if _open() created the suspend blocker giving it a name based on
the name of the process that called it.  Something like
"<process name>_<timestamp>" might work at first sight.

Alternatively, "<process_name><number>", where <number> is 0 for the first
suspend blocker created by the given process, 1 for the second one etc., also
seems to be doable.

Rafael