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From: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>
Subject: Re: [Qemu-devel] How are the temporary files (-snapshot) created on
	Linux?
Date: Fri, 12 Sep 2008 12:18:50 +0200
References: <20080912080402.1m7hh8oc0sgs4wsw@www.idoru.ch>
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To: qemu-devel@nongnu.org
Cc: EQX <eqx@gmx.net>

Hello!

On Friday 12 September 2008 08:04:02 EQX wrote:
> The code says the -snapshot temporary files are created here:  
> /tmp/vl.*, but they are never visible for users. Using lsof, they have  
> a state of 'deleted'. How does this work exactly? What type of file is  
> this?

It's done via some incantation of open(2) followed by unlink(2), something
like:

  int fd;
  fd = open( "/tmp/vl.xxx", O_CREAT|... );
  unlink( "/tmp/vl.xxx" );
  /* Use the file somehow */
  close( fd );

Regards,
Yann E. MORIN.

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