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Date: Sat, 25 Jun 2016 10:02:38 +0300
From: Konstantin Belousov <kostikbel@gmail.com>
To: Brooks Davis <brooks@freebsd.org>
Cc: freebsd-current@freebsd.org
Subject: Re: HEADS UP: caution required with updates using custom kernels
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On Fri, Jun 24, 2016 at 10:50:34PM +0000, Brooks Davis wrote:
> pipe(2) had an unnecessarily odd calling convention (ignoring the
> argument the user thought they were passing and returning the two file
> descriptors via the two return registers).  This required machine
> dependent assembly for every target and special handling in tracing
> tools (ktrace, dtrace, etc).  On 64-bit platforms, pipe(2)'s
> implementation is the only reason the two-register return model needs to
> exist at all (on 32-bit platforms it allows off_t to be returned from
> lseek).
getpid() is another instance.