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Date: Mon, 23 Apr 2001 23:09:44 +0100 (BST)
From: Matt <madmatt@bits.bris.ac.uk>
To: linux-kernel@vger.kernel.org
Subject: Re: ioctl arg passing
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Matt mentioned the following:

| struct instruction_t {
| 	__s16 code;
| 	__s16 rxlen;
| 	__s16 *rxbuf;
| 	__s16 txlen;
| 	__s16 *txbuf;
| };

So far, I now know I can grab stuff across the user <-> kernel divide as I
planned. The only problem I'm left with, which was kindly pointed out to
me, is a question of packing with respect to both kernel & user-space.

Can anyone suggest a method of either assuring the above structure is
always packed the same, or alterations so that the problem is
minimised? Either splitting the one ioctl into many, etc.

Thanks

Matt

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