From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ken Goldman <kgoldman-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
Subject: TPM 2.0 device driver blocking open
Date: Fri, 30 Dec 2016 10:53:26 -0500
Message-ID: <o45vtc$ur$1@blaine.gmane.org>
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It appears that an open() to the TPM doesn't block if another process 
has /dev/tpm0 open.  It returns -1, an error.

Questions:

Is this expected behavior?
Was this also true for 1.2?
Is there any way to change it.  I didn't set O_NOBLOCK.  Is there 
perhaps an ioctl()?
Is this something that should be added?


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