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Date: Fri, 22 May 2009 16:32:32 -0600
From: Cam Macdonell <cam@cs.ualberta.ca>
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Subject: [Qemu-devel] Passing fds through a qemu char device
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To: qemu-devel@nongnu.org


Hi,

I'm trying to pass eventfds between qemu processes and I'm trying to use 
a qemu char device to do this.  AFAICT with a qemu_chr_device the 
polling handler only has support to call read()/write(), not 
send/recvmsg() which are necessary to send and receive fds with 
SCM_RIGHTS through the socket.  Is this true or is there support in Qemu 
for recvmsg() that I'm not seeing?

If not, some options I can see are to add qemu support for 
qemu_chr_recvmsg() to call on the char device.  Or I can simply manage 
the socket outside of qemu_chr_device, but the polling is helpful for 
notifications and I'd prefer to leverage qemu's existing support for that.

Thanks,
Cam